LEGO Harry Potter 76386 Polyjuice Potion Mistake Review

LEGO 76386 Polyjuice Potion Mistake is a 217 piece set, part of the modular LEGO Harry Potter Hogwarts collection. The set creates the scene from Harry Potter and The Chamber of Secrets, where Harry, Hermione and Rupert attempt to create Polyjuice in the Hogwarts bathroom.

Polyjuice enables the consumer to shape-shift, except they get it wrong – with hilarious results! Read on for our full review.

Lego Harry Potter Hogwarts: Polyjuice Potion Mistake box

Set Information

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LEGO Harry Potter Hogwarts: Polyjuice Potion Mistake is a modular set that combines with 76389 Hogwarts Chamber of Secrets and 76387 Hogwarts: Fluffy Encounter to form one giant Hogwarts set that looks absolutely epic.

That said, 76386 Polyjuice Potion Mistake is a fun little set all on its own, and absolutely doesn’t require owning the other two in the collection to be enjoyed.

All of the parts included in Lego Hogwarts Polyjuice Potion Mistake

The Build

The build is set in Hogwarts girls’ bathroom, where Harry, Hermione and Rupert are attempting to create Polyjuice, a potion that enables the consumer to shape-shift into another shape of the same species.

The trio suspect that Malfoy is the heir of Slytherin, so they plan to shift into Slytherin students and use their disguise as an opportunity to question Malfoy themselves.

Hermione, Harry and Rupert stood on the front of the Polyjuice Potion Mistake Lego set

The build starts with creating the shell of the bathroom, which is built in the same style as the larger Harry Potter Hogwarts sets. The internal detail is then fleshed out, which includes a toilet cubicle and three sinks.

The sinks include a good amount of detail for a small set, including gold tap bricks and use of white barrels to create a pillar effect surrounding the mirrors. The mirrors are created by the only stickers included, which attach to grey bricks. Everyone likes to moan about stickers, but expecting mirrored bricks in a £18 set is probably a bit excessive.

Whilst still talking about sinks and mirrors, it’s worth noting that the central sink unit hides a secret passage to the floor below. If you only have this set then it’s a secret passage to nowhere – something I found a little annoying, but didn’t seem to phase my four year old.

Lego Polyjuice Potion Mistake with the secret passage through the middle sink open

A couple of extra plates to plug the hole would have been a welcome addition, otherwise it’s an easy mod for those that care enough. The secret passage was quickly packed with the extra minifig hair pieces and bonus Wizard Cards (more on those below).

Showing the bottom of 76386 Polyjuice Potion Mistake where it would be easy to plug the secret gap with a few Lego plates

The exterior of the set continues the Hogwarts theme, using the same colour pallette and window detailing. Due to the positioning of the window being behind the secret sink section it’s not possible to see through it, but the fact the detail is included is a welcome addition and breaks up an otherwise reasonably bland wall.

The window detail on the back of Lego Polyjuice Potion Mistake

The only repeated section of the build are the left and right bathroom mirror sections. They only took a few minutes each so weren’t enough to cause any “can we play with it yet?” comments from my four year old son!

Modular fans will recognise the studded tiles on the top of the walls. These are used to position the set against the other two in the LEGO Harry Potter Chamber of Secrets collection. Same goes for the Technic connectors, but these are used to connect the set horizontally to other sets in the collection.

Characters and Collectables

Four minifigs are included – Harry Potter, Hermione Granger, Rupert Grint and a bonus golden Harry Potter.

Rupert Grint, Hermione Granger and Harry Potter, the minifigures included with Lego 76386

The minifig legs included are of the short variety, so the leg positions are fixed and they’re unable to sit down. Additionally there is no detail on the legs as there is with the larger Harry Potter minifig legs.

It’s also worth pointing out that the minifig heads on the boys are making an appearance for the first time in this set!

Golden Harry Potter minifigure, included with Polyjuice Potion Mistake

The gold minifig is part of the 2021 Harry Potter 20th anniversary celebration – it does make me feel slightly old knowing that I saw the first movie in the cinema! The additional minifig is a nice touch, and also a cunning way to persuade avid collectors to pick up the other sets in the 20th anniversary collection.

Back of the Harry Potter Golden minifigure, showing the 20th anniversary logo

Those familiar with the Chamber of Secrets story will know that Harry, Hermione and Rupert use Polyjuice to change into Slytherin students with a plan to extract information from Malfoy.

Harry and Rupert successfully turn into Gregory Goyle and Vincent Crabbe respectively. However, Hermione’s potion accidentally contains a cat’s hair, and her attempt to turn into Millicent Bulstrode ends with her partially turning into a cat!

The minifigs all include extra faces and hair to play out this part of the story, a really nice touch for a small set! The eagle-eyed minifig collectors will notice that the cat minifig hair hasn’t been seen before and was produced for this set.

Showing the minifigures in their post-Polyjuice form including Hermione as a half cat

All LEGO Harry Potter sets include random Wizard Tiles, a 2×2 purple tile with a Harry Potter character printed on them. This set is no exception, and includes two Wizard Tiles. The instructions show all of the possibilities to collect, as well as giving you somewhere to tick off the tiles you’ve already collected.


How many pieces are there in LEGO 76386 Polyjuice Potion Mistake?

The set contains 217 pieces.

How long does it take to build LEGO 76386 Polyjuice Potion Mistake?

It took my four year old son approximately an hour to build.

How many minifigs are included in LEGO 76386 Polyjuice Potion Mistake?

The set includes four minifigs. Three are normal Harry Potter characters – Harry Potter, Hermione Granger and Rupert Grint, and one is a gold collectable Harry Potter. All four have short minifig legs that don’t move or allow the minifig to sit. The set includes additional hair that change Harry into Gregory Goyle, Rupert into Vincent Crabbe, and Hermione into a cat/girl hybrid.

How many Wizard Tiles are included in LEGO 76386 Polyjuice Potion Mistake?

The set includes two random Wizard Tiles.

What unique parts are included in LEGO 76386 Polyjuice Potion Mistake?

Aside from the golden Harry Potter minifigure, the heads on Harry and Rupert, Hermione’s cat hair, and the clear and green goblet.

Final Thoughts

My four year old son completed the build of LEGO Harry Potter Hogwarts: Polyjuice Potion Mistake his own, with me only helping to find parts and stick the bathroom mirror stickers. It took us about an hour, and there were enough interesting parts and minifigs included to keep his attention, and the build moving forward.

If you or your child is a Harry Potter fan, then at only £17.99 this set is an absolute steal. It consists of a nice build, four minifigs, and enough parts and props to concoct fun stories based around the wider Harry Potter theme.

If you’re lucky enough to own either of the adjoining LEGO Harry Potter sets – 76389 Hogwarts Chamber of Secrets or 76387 Hogwarts: Fluffy Encounter, then Polyjuice Potion Mistake is an awesome little set to add to the collection, and definitely shouldn’t be missed!

Pick up your copy of the set from Amazon.

Have you bought LEGO Harry Potter 76386 Hogwarts: Polyjuice Potion Mistake? Did you buy it for the set or the collectables? Let us know in the comments!

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