LEGO Harry Potter Diagon Alley 75978 Review & Lighting Journal

It’s been a big year for LEGO Harry Potter fans, with a large number of hugely popular kits released this year including the instant classics Attack On The Burrows and Hogwarts Astronomy Tower. But it appears LEGO have saved the best and certainly the BIGGEST for the end of the year. That’s right, we’re all talking about the new LEGO Harry Potter Diagon Alley modular building set!

The buzz around this set has been high for several reasons, you want to talk numbers? Let’s talk some numbers. First, the sheer size of the set - a massive 5544 pieces, (making it the second largest Harry Potter set on the market only behind Hogwarts Castle itself), seven separate stores represented across four individual modular buildings, 14 mini figures and over a meter wide when arranged end to end! Demand for this set has been incredibly high and we can totally see why. Harry Potter is one of the most popular LEGO themes and the famous London street is a fan favorite location in both novel and film form.

We mentioned the modular nature of the set, what makes this set different from other modular buildings is that each store is represented by facade only, or rather the backs are open in a dollhouse fashion. This is interesting and ingenious for two reasons, the first is that this allowed the designers to cram double, triple, quadruple the amount of detail into each buildings interior all of which begs to be played with. Second and most notably, this allows each modular plate to be arranged and rearranged in as many combinations as the builders sees fit - exactly like the magically alleyway in the world of Harry Potter! Nothing is ever quite as it seems and bricks, tiles and archways move and shift before your eyes!

Now if you’ve been around these parts for long, you’ll know that all of us here at LMBHQ are big time Potterheads, so you know we were quick on our wand fingers to hit purchase the moment LEGO released it! Every day until it arrived our post man was hassled.

If you were watching on our Instagram stories, you may have seen it arrive and us tear into the packaging immediately to get started with the build - and what packaging! There were so many bags, boxes and buildings we weren’t sure where to begin! (and what of this secret box?) Luckily there was no shortage of builders in the office who were keen to take on one of the baseplates. The fact that the set is made up of four modular buildings that can be built independently of each other meant we were all able to get to work at once, speeding up the construction process considerably.

One thing that stood out to all of us, was the use of colour to break up and differentiate each building. First of all the colors really do look great, but also serve to highlight a lot of the fun details that have been included from the films. Spell books, broomsticks and news papers are all here on view and the dolls house style build really encourages play. The use of color along with the design makes the set feel like four fun individual builds, rather than a solitary set.


Of course we can’t skip over these awesome mini figures, as we mentioned and enormous 14 in total (or is that 16?). All unique to the set, with returning characters decked out in brand new outfits. The father and son Malfoy duo likeness is spot on.

Once the build was finally complete it was time to take on the task of lighting the famous magical street. We must say things were a little different this time around. The last Harry Potter kit we produced was the Clock Tower and we had the benefit of having previously designed the kits for both the Great Hall and the Whomping Willow. These three kits are very similar because the LEGO sets join together to form a larger Hogwarts set.

The first task was an obvious one to address, but unique in the challenge it presented and that was lighting each building appropriately while keeping their modular functionality in tact. The buildings had to look great in a single open row AND great when arranged facing each other 2x2 to create an alley effect. It was a very delicate balance, too much light in the open form meant that it was overlit in alley form. Not enough light on the other hand, left the buildings underwhelming.

It’s challenges like this that see some kits take a little longer to hit the market, we’re not looking to drench every LEGO set we get our hands on like a Friday night football field. We want to make sure we get it right, do the set justice and deliver a product that fans of the source material will be satisfied with. Because we’re fans ourselves!

The display window of Quality Quidditch Supplies was particularly agonized over. How to make sure that Nimbus 2000 was lit according to the film, without the glare over saturating the rest of the building? Many combinations were trialed but ultimately it was the sparsely used Large White Bit Light all on it’s own that spotlighted the pro model broomstick.


There was one afternoon in particular where 4 designers we huddled around Flourish and Blotts figuring out the perfect way to light the exterior of the building “like this?… how about this?…. maybe a little to the left.” A funny sight to see, but we love lighting LEGO and are passionate about pushing the hobby to the next level. This is the perfect set to do just that.

Using film frames as reference, we continually installed, iterated and innovated to ensure the lighting and atmosphere was as true to the film as possible.

The only exception to our rule of not over doing the lighting was perhaps Weasley’s Wizard Wheezes. After cracking a tricky build situation, we figured out how to insert a Multi Color Strip Light to replicate the changing colored lights made famous in The Half Blood Prince. While that particular film in the wizarding series is lit quite darkly from a cinematic point of view, the store itself is full of life, light, sparks and flashes. The Multi Color Light String certainly brings all of these elements to the table! There was some fierce debate as to whether it was too overpowering as compared to the other three buildings, but ultimately it will come down to personal preference in the Light My Bricks customer. It’s no problem to disconnect the light string if you’re the kind of hobbyist who prefers a more subtle look. That’s the great things about our kits, totally customizable at every stage of assembly!


Finally, with each modular building completed and the balance just right, it was time to sit back and admire our handiwork! After many hours of planning, testing, lighting and creating, the famous Wizarding street was finally finished. Both in linear form and in alley form we couldn't be happier with the result!

Which is your favorite? Will LEGO add stores with another set?

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