Last updated at 06/09/2026 10:53:03
Lego 70437 Hidden Side Mystery Castle Brand New, Sealed, Retired
Free delivery
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LEGO 70437 - Hidden Side Mystery Castle
Delivery between 9–17 Sept $10
LEGO 70437 - Hidden Side Mystery Castle
Delivery between Wed – Sat $10
originally posted on LEGO
This is a great addition to our Legos. My girls absolutely love mysteries and this castle did not disappoint and is one of their favorites. This set has amazing attention to detail and the castle is quite sturdy and has stood up well during play. The minifigures are great and one of our favorite parts. It has already been hours of fun, highly recommend.
originally posted on LEGO
This set was a hit for adults and kids alike. Really fun build and very appealing visually. Tons of unique interactive elements like a trap door, many levels of the building, moving pieces, so it really lends itself to a kid's imagination with the characters too. The game on the app is a fun experience too once you get the hang of it and unlock more features. Definitely recommend this set.
originally posted on LEGO
This LEGO Mystery Castle is amazing! Such a fun project to build with the family.A challenging build, that will take time and focus. But provides hours of entertainment for all.We have assembled and re-assembled it twice already.The mystery side is another gem of the build, not completly knowing what it looks like until completed. You can also modify it many ways.We will continue to experiment and build many more times. Adding to our Lego family.
| Features | |
| Release date (DD/MM/YYYY) | 01/07/2020 |
| Sound effects | N |
| Number of pieces | 1035 pc(s) |
| Recommended age (max) | 99 yr(s) |
Lego 70437 Hidden Side Mystery Castle Brand New, Sealed, Retired
Free delivery
Affiliate Disclosure: We may receive a small commission for purchases made through this link at no extra cost to you. This helps support our site. Thank you!
LEGO 70437 - Hidden Side Mystery Castle
Delivery between 9–17 Sept $10
LEGO 70437 - Hidden Side Mystery Castle
Delivery between Wed – Sat $10
This is a great addition to our Legos. My girls absolutely love mysteries and this castle did not disappoint and is one of their favorites. This set has amazing attention to detail and the castle is quite sturdy and has stood up well during play. The minifigures are great and one of our favorite parts. It has already been hours of fun, highly recommend.
This set was a hit for adults and kids alike. Really fun build and very appealing visually. Tons of unique interactive elements like a trap door, many levels of the building, moving pieces, so it really lends itself to a kid's imagination with the characters too. The game on the app is a fun experience too once you get the hang of it and unlock more features. Definitely recommend this set.
This LEGO Mystery Castle is amazing! Such a fun project to build with the family.A challenging build, that will take time and focus. But provides hours of entertainment for all.We have assembled and re-assembled it twice already.The mystery side is another gem of the build, not completly knowing what it looks like until completed. You can also modify it many ways.We will continue to experiment and build many more times. Adding to our Lego family.
The Good- It looks great, a very cool castle and fun to build. And a great value for the money. The coloring was great and I love the astronomy tower. VERY COOL!. I was a huge fan of the Hidden Side. It has a long time between now and the Monster Fighters. We need more Horror based sets, at at least Universal Monster based sets that aren't corny.The bad, which is just my opinion, and should take away from how cool the set really is. To many stickers and No Painted bricks. I would have like to have a skeleton or something in 1 of the 2 dungeons. Rooms are kinda small and not much goes in them. Could of had more minifigs. IE Skeleton or a prisoner. replace of of the guards with something else. It deserves 4.5 stars.FYI My favorite set so Far is the new Haunted ... MoreThe Good- It looks great, a very cool castle and fun to build. And a great value for the money. The coloring was great and I love the astronomy tower. VERY COOL!. I was a huge fan of the Hidden Side. It has a long time between now and the Monster Fighters. We need more Horror based sets, at at least Universal Monster based sets that aren't corny.The bad, which is just my opinion, and should take away from how cool the set really is. To many stickers and No Painted bricks. I would have like to have a skeleton or something in 1 of the 2 dungeons. Rooms are kinda small and not much goes in them. Could of had more minifigs. IE Skeleton or a prisoner. replace of of the guards with something else. It deserves 4.5 stars.FYI My favorite set so Far is the new Haunted House- No decals and lots of nice looking Painted bricks and great minifigs.
Legos are a favorite past time at my house. From picking our next set, to working as a team to build it. My kids are always excited when we complete our LEGO set. What makes this Mystery Castle even funnier is the interactive ability with a mobile device.With larger sets like this one, it takes us at least three days to build. My kids do most of the building and I help with the hard parts. For most of the build my 10 and 8 year old could snap the pieces together, an adult had to assist a couple of times. I really appreciate how the bags are labeled with numbers and that it’s broken up into separate stages. At the end of every bag you always have spare pieces, which is a great idea, incase one of the smaller pieces gets misplaced.I’m always impressed with the ... MoreLegos are a favorite past time at my house. From picking our next set, to working as a team to build it. My kids are always excited when we complete our LEGO set. What makes this Mystery Castle even funnier is the interactive ability with a mobile device.With larger sets like this one, it takes us at least three days to build. My kids do most of the building and I help with the hard parts. For most of the build my 10 and 8 year old could snap the pieces together, an adult had to assist a couple of times. I really appreciate how the bags are labeled with numbers and that it’s broken up into separate stages. At the end of every bag you always have spare pieces, which is a great idea, incase one of the smaller pieces gets misplaced.I’m always impressed with the instructions. This set was larger and the booklet was easy to follow. Both my kids love being able to read the easy step by step pages. Having detailed pictures is great!My children not only enjoyed building this castle, but also bringing it to life. We used the app on my phone to scan the build with the camera. It’s super neat how you can fight ghosts and see them flying around on your device. It’s an easy game and makes legos even more fun. You do need a newer device to play, so an older phone or tablet won’t work. I have an iPhone 7 which can play the interactive game.My kids and I are looking forward to more LEGO Hidden Side builds and can’t wait to put together our next set.
I wanted this Castle for myspooky Halloween setupfor indoors & I was notdisappointed. Upon completion, castle , entrance way, rear view &observatory are very distinctive, observatorycompletion was difficult formy old fingers & I thoughtplacement of certain partscould have had better pictures to facilitate matching dome , did someglue work, plan on keeping itintact for couple more Halloweens.I can only remark that I wish there were kits like this 60yrs ago,I am now in my 3rd childhood, very therapeutic, as another builder referenced. I have too many of these Hidden Side items,will concentrate on Winter scenes.
The Lego Hidden Side Mystery Castle was so much fun to build. My daughter spent the whole day off and on building the castle. The instructions are detailed and the pieces are split up into separate packaging to make it easier to organize and build. This was a great indoor activity to keep kids busy and at the same time learning about how structures work. As I've come to expect from Lego, the pieces all fit perfectly and there were some extras of the smaller pieces just in case they got misplaced. Building it was not too challenging especially for a teen, but may be a little more challenging for kids under 10. However, that being said, it's a great activity that teaches a lot about building in general.Another thing I liked was the details in the set. From the ... MoreThe Lego Hidden Side Mystery Castle was so much fun to build. My daughter spent the whole day off and on building the castle. The instructions are detailed and the pieces are split up into separate packaging to make it easier to organize and build. This was a great indoor activity to keep kids busy and at the same time learning about how structures work. As I've come to expect from Lego, the pieces all fit perfectly and there were some extras of the smaller pieces just in case they got misplaced. Building it was not too challenging especially for a teen, but may be a little more challenging for kids under 10. However, that being said, it's a great activity that teaches a lot about building in general.Another thing I liked was the details in the set. From the miniature piano to the "stained glass" windows and moving parts within the set, there were so many details that made this set worth every penny. My absolute favorite part about the castle though was the innovative technology that was built in. I love that there was an app to download after you build the set and you can actually play games and "catch ghosts" virtually. So not only does it give kids something to do while they build, but becomes a long term activity as well. What's also great is that this isn't just limited to kids; it's a great model to build for anyone and looks great as a show piece in the home as well. I am so very impressed with the Mystery Castle and highly recommend it to anyone looking for an activity that is fun, innovative and imaginative.
This is my favorite set! Where to start, where to start... This set looks so amazing on display, it's unbelievable. The figures are all pretty cool, especially Vaughn Geist. When I get my LEGO sets, what I usually do is build it, extract the figures to play with, then put the set itself on my shelf, so sets that look really good on display are usually the sets I lean towards, and this one looks AMAZING! Anyway, if you're like me and are more looking for display then play, this is your set. If you're more into play... not so much.
Got this set for a dark fantasy MOC I've been building. I got the Monster fighters castle set so I can compare.The good:Decent display piece.Castle opens up inviting play, is also very sturdyMain Badguy mini-figure is awesomeThe colours look great.The Bad:Rooms themselves feel lacking in details. 2 prison cells with nothing in them...The mouth moving/trapdoor play feature is mehLight green parts SHOULD glow in the dark like monster huntersIt feels like they were trying to make an improved version of monster fighters. But I feel as though is less interesting all up. It's a solid purchase for castle stuff but would not say essential.
We LOVE Legos. We have a table dedicated to lego building and own a lot of sets. But when Lego came out with Hidden Side, I knew I needed to add it to my family's collection. We are huge fans of horror and all things spooky. So this was right up my alley. The Hidden Side Mystery Castle is everything I want in a set. The detail is fantastic and it's fun to put together. The height of the castle is perfect and the set is very durable. The characters are awesome and really bring this set to life. Not only do the characters bring this set to life, but the interactive app is so much fun! You can see the ghosts and play games in your Hidden Side virtual world. You become the ghost hunter or even ghosts if you play with friends. It takes the fun to a whole new level that ... MoreWe LOVE Legos. We have a table dedicated to lego building and own a lot of sets. But when Lego came out with Hidden Side, I knew I needed to add it to my family's collection. We are huge fans of horror and all things spooky. So this was right up my alley. The Hidden Side Mystery Castle is everything I want in a set. The detail is fantastic and it's fun to put together. The height of the castle is perfect and the set is very durable. The characters are awesome and really bring this set to life. Not only do the characters bring this set to life, but the interactive app is so much fun! You can see the ghosts and play games in your Hidden Side virtual world. You become the ghost hunter or even ghosts if you play with friends. It takes the fun to a whole new level that will make you want to collect all the sets. It is the most fun I've ever had with a Lego set series. I highly recommend to anyone
| Features | |
| Release date (DD/MM/YYYY) | 01/07/2020 |
| Sound effects | N |
| Number of pieces | 1035 pc(s) |
| Recommended age (max) | 99 yr(s) |
LEGO 70437 Hidden Side Mystery Castle
This LEGO Hidden Side building kit combines the open creative play of LEGO building toys with digital play for an immersive single or multiplayer augmented reality (AR) experience A digitally interactive LEGO Hidden Side castle model with lots of manual features including an accessible observatory tower, plus Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures The mystery castle model comes to life when viewed through a smart device equipped with the free LEGO Hidden Side AR app; Kids then get to solve mysteries, find items and hunt ghosts in a haunted digital world This action-packed LEGO Hidden Side playset is a great gift idea for LEGO builders aged 9 and up and fans of virtual reality and video games When built, this LEGO Hidden Side Mystery Castle (70437) augmented reality playset measures over 13" (34cm) high, 12" (31cm) wide and 10" (27cm) deep Fans of virtual reality and video games love the amazing LEGO Hidden Side universe, where physical and digital worlds meet to provide an incredible, single or multiplayer augmented reality (AR) play experience. This LEGO Hidden Side Mystery Castle 70437 playset combines a buildable LEGO model with an app, so interaction with the model triggers events in a digital world. The mystery castle springs to life when viewed through a smart device with the LEGO Hidden Side AR app. Children then get to explore, solve mysteries, hunt ghosts and battle boss ghost The Maw in an exciting digital world. The possessed castle model also folds out, setting the scene for action-packed role play with the Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures. The LEGO Hidden Side universe is set in the fictional town of Newbury, where ghosts haunt people and buildings. The AR play experience is constantly enhanced through new content, characters and special events.
This LEGO Hidden Side building kit combines the open creative play of LEGO building toys with digital play for an immersive single or multiplayer augmented reality (AR) experience A digitally interactive LEGO Hidden Side castle model with lots of manual features including an accessible observatory tower, plus Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures The mystery castle model comes to life when viewed through a smart device equipped with the free LEGO Hidden Side AR app; Kids then get to solve mysteries, find items and hunt ghosts in a haunted digital world This action-packed LEGO Hidden Side playset is a great gift idea for LEGO builders aged 9 and up and fans of virtual reality and video games When built, this LEGO Hidden Side Mystery Castle (70437) augmented reality playset measures over 13" (34cm) high, 12" (31cm) wide and 10" (27cm) deep Fans of virtual reality and video games love the amazing LEGO Hidden Side universe, where physical and digital worlds meet to provide an incredible, single or multiplayer augmented reality (AR) play experience. This LEGO Hidden Side Mystery Castle 70437 playset combines a buildable LEGO model with an app, so interaction with the model triggers events in a digital world. The mystery castle springs to life when viewed through a smart device with the LEGO Hidden Side AR app. Children then get to explore, solve mysteries, hunt ghosts and battle boss ghost The Maw in an exciting digital world. The possessed castle model also folds out, setting the scene for action-packed role play with the Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures. The LEGO Hidden Side universe is set in the fictional town of Newbury, where ghosts haunt people and buildings. The AR play experience is constantly enhanced through new content, characters and special events.
This LEGO Hidden Side building kit combines the open creative play of LEGO building toys with digital play for an immersive single or multiplayer augmented reality (AR) experience A digitally interactive LEGO Hidden Side castle model with lots of manual features including an accessible observatory tower, plus Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures The mystery castle model comes to life when viewed through a smart device equipped with the free LEGO Hidden Side AR app; Kids then get to solve mysteries, find items and hunt ghosts in a haunted digital world This action-packed LEGO Hidden Side playset is a great gift idea for LEGO builders aged 9 and up and fans of virtual reality and video games When built, this LEGO Hidden Side Mystery Castle (70437) augmented reality playset measures over 13" (34cm) high, 12" (31cm) wide and 10" (27cm) deep Fans of virtual reality and video games love the amazing LEGO Hidden Side universe, where physical and digital worlds meet to provide an incredible, single or multiplayer augmented reality (AR) play experience. This LEGO Hidden Side Mystery Castle 70437 playset combines a buildable LEGO model with an app, so interaction with the model triggers events in a digital world. The mystery castle springs to life when viewed through a smart device with the LEGO Hidden Side AR app. Children then get to explore, solve mysteries, hunt ghosts and battle boss ghost The Maw in an exciting digital world. The possessed castle model also folds out, setting the scene for action-packed role play with the Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures. The LEGO Hidden Side universe is set in the fictional town of Newbury, where ghosts haunt people and buildings. The AR play experience is constantly enhanced through new content, characters and special events.
This LEGO Hidden Side building kit combines the open creative play of LEGO building toys with digital play for an immersive single or multiplayer augmented reality (AR) experience A digitally interactive LEGO Hidden Side castle model with lots of manual features including an accessible observatory tower, plus Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures The mystery castle model comes to life when viewed through a smart device equipped with the free LEGO Hidden Side AR app; Kids then get to solve mysteries, find items and hunt ghosts in a haunted digital world This action-packed LEGO Hidden Side playset is a great gift idea for LEGO builders aged 9 and up and fans of virtual reality and video games When built, this LEGO Hidden Side Mystery Castle (70437) augmented reality playset measures over 13" (34cm) high, 12" (31cm) wide and 10" (27cm) deep Fans of virtual reality and video games love the amazing LEGO Hidden Side universe, where physical and digital worlds meet to provide an incredible, single or multiplayer augmented reality (AR) play experience. This LEGO Hidden Side Mystery Castle 70437 playset combines a buildable LEGO model with an app, so interaction with the model triggers events in a digital world. The mystery castle springs to life when viewed through a smart device with the LEGO Hidden Side AR app. Children then get to explore, solve mysteries, hunt ghosts and battle boss ghost The Maw in an exciting digital world. The possessed castle model also folds out, setting the scene for action-packed role play with the Jack, Parker, Vaughn, Nehmaar Reem and 2 Shadow-Walker minifigures. The LEGO Hidden Side universe is set in the fictional town of Newbury, where ghosts haunt people and buildings. The AR play experience is constantly enhanced through new content, characters and special events.
in 3 offers
The lowest price for LEGO 70437 Hidden Side Mystery Castle right now is $280.46 at eBay.com.au, compared across 3 retailers.
The all-time low was $99.95 on 6 June 2026 — today's price is 181% above the lowest ever. It has been notably cheaper before — worth setting a price alert.
Prices last updated 6 Sept 2026.
