Between the lucrative high profile movie tie-ins and people begging for Zelda and Mega Man editions, it's sometimes easy to overlook the fact that The LEGO Group cut its teeth on its non-licensed playsets. From fantasy wonderlands to more ordinary examples, the building bricks were an ever-popular force with children and big kids alike long before LEGO Star Wars rolled along.

Though there have been several games based on LEGO's own series – 1997's LEGO Island often evokes murmurs of admiration – the licensed titles are still top of the blocks. LEGO City Undercover could be the game to begin deconstructing that set up. Based on the LEGO City line, which sees firemen, farmers and foremen transformed into heroes of a more relatable nature, TT Fusion's title takes the formula that has been popularised by licenced properties and applies it to a series of LEGO's own design.

You're Chase McCain, expert detective and master of disguise. Once exiled from LEGO City for reasons unknown – we'll find out why soon enough in 3DS prequel LEGO City Undercover: The Chase Begins – McCain has been summoned back into town to track down old foe and recent prison escapee Rex Fury. With the added incentive of an old flame to reignite, Chase wastes no time in donning as many outfits as possible to get Rex back behind bars in true cop action movie style.

With no existing franchise to pander to, LEGO City Undercover is a giant play bucket of ideas and humour. It's a stellar effort that actually feels stronger for the lack of licence, though it doesn't make the most of its freedom. It doesn't stray too far from other recent LEGO titles when it comes to structure, for instance: though there's now a reasonably-sized open world to zoom around, many missions still take place in self-contained levels cut away from the city streets. In these you solve simplistic puzzles that usually revolve around breaking and repairing parts of the environment, leap over platforms and fight groups of bad guys in a responsive, reversal-centric combat system that's easy to pick up. The setting is perfect for putting Chase through numerous locations — there are museums filled with LEGO dinosaurs, sewers, mansions and construction sites, all of which provide different gimmicks to play with and loads to dismantle.

It feels like an evolution of LEGO Batman 2: DC Super Heroes, and that's definitely no bad thing. LEGO City is full of things to do: there's basic platforming, acrobatic rooftop free-running and, of course, lots of smashing, building and collecting of LEGO studs. The streets are practically paved with gold and silver studs, which rapidly regenerate whenever you turn your back for a minute: snatching up every one is as dangerously addictive as ever, and you'll need all you can get if you want to purchase all the unlockable costumes and vehicles.

Throughout the story Chase gets the chance to dress up in several key outfits: starting out with his police uniform, he progresses to burglar garb, miner duds and more. As in other LEGO titles, each costume type lets him use different abilities. He can soar to new heights with the police officer's grappling hook, put out infernos and rescue helpless kittens as a fireman and crack open safes and doors as a thief. As well as being used in missions, these disguises also unlock secret areas and side missions – additional things to collect — in the city. You'll need to master them all to discover everything and earn all 450 golden bricks.

The Wii U GamePad is a fairly integral part of the game. McCain has his own version of the controller, which acts as a police device used to communicate with other characters and to search for criminal activity; his can light up footprints with a UV light. Throughout the story you receive regular video calls on the GamePad, and at key moments you're invited to hold it up to the television to scan for criminals or decrypt audio conversations.

You can use a similar mechanic to locate hidden items, though unfortunately you can only tag one thing at once. It's also a shame that some of these functions are restricted to special locations – it really limits their usage, and the same applies to items such as the grappling hook, which only lets you climb at certain points rather than letting you zip all over the place.

There's a camera application that can be used whenever you like, though – well, at least when your feet are on the ground. You can snap a full screenshot, or you can take it into first-person mode and capture things from Chase's perspective. Images can apparently be shared on Miiverse from within the game, without opening the home menu and manually entering the social network, but at the time of writing the LEGO City Undercover Miiverse community was unavailable, so this couldn't be tested.

When it's not being used for more fanciful purposes, the GamePad provides a full-screen map. It's surprisingly useful and convenient, especially since you can tap anywhere to set a desired destination whenever you're not in a mission. As well as a stream of green studs leading the way on screen, a helpful trail is also drawn over the roads on the map, sat nav-style.

As if LEGO studs weren't enough to collect, there's an additional form of currency in LEGO City Undercover. Now you can grab bricks that scatter onto the ground whenever you demolish something – hint: all the time – that can then be used to put together Super Builds that are dotted around the city. These glowing panels can, provided you have enough bricks, become call points for any vehicles you've unlocked, helipads, stunt ramps, statues and more. Brilliantly, if you crash into anything made of LEGO while driving, you get bricks; chain together destruction and you can build up multipliers to capture even more. A simple drive down a street often becomes a rollercoaster ride of bashing through bollards and tearing down lampposts. Don't worry, you can't hurt any LEGO people — they all dive comically out of the way.

Compared to other open world titles, LEGO City Undercover's map is quite small. It takes a little while to drive around, but it's nothing when put up against a game like Just Cause 2, for example. However, it has a good deal of variety — from docks and islands to a bustling Times Square-like area and tranquil wildlife-filled woodlands — and is packed with things to do. It's not all smashing and grabbing either – though that does make up a significant portion of it. You can get involved with car chases, launch off stunt ramps, drive around in boats, aircraft and trams, plus discover delightful hidden Nintendo nods. We're not going to spoil any of them, but look around carefully and you're sure to spot one or two along the way, whether they're tucked away on flags or make themselves explicitly known with a grin-inducing musical flourish.

The size of the city doesn't matter; it feels appropriate to the series and we had just as much fun boosting around it in the first five minutes as we did in our 25th hour. And if you want proof that there's tons to find: we completed the main story in about 18 hours, and with a further seven hours of play on top of that our save file is still only around 30% complete.

There are some technical issues that weigh down on LEGO City Undercover, but none so bad that they ruin the game. There are abysmal loading times under certain circumstances – loading up the save file, entering and exiting the police station, generally anything that involves pulling in the whole city after an environment swap. These can last between 30 and 60 seconds in the worst instances, but thankfully they're relatively infrequent.

Once the open world is loaded there are no issues: it all streams along smoothly, with only the odd insignificant frame rate drop here and there, presumably when it's loading in further content. There are some obvious cases of pop-in, though nothing that affected gameplay – we'd chalk these things up to the challenge of developing an open world title for a new console.

It would have been good to see further anti-aliasing, however. The visuals are nice, about on level with recent HD LEGO titles on Xbox 360 and PlayStation 3, but there are jagged edges all over the place, and not just from the bricks. If you're sat a healthy distance from the TV it's not a massive problem, and you're not likely to be offended by it during movement, but it is rather apparent if you stop still and look about. On the plus side, we didn't spot any screen tearing and there are some decent motion blur effects.

More problematic are the driving controls, which are loose with certain vehicles. There's not much trouble with basic cars, but hop on a super-fast bike and an ill tilt of the analogue stick can have you smashing into a building on the other side of the street. We only failed missions on a few occasions; when we did it was usually because we were driving a lorry that didn't do as it was told. With a bit of trial and error you soon work out which vehicles are "safe" to drive.

Yet it's easy to forgive a game like LEGO City Undercover. It's clearly a labour of love and, while it might not be the most polished title, it's one of the funniest games we've played in ages. Those tiresome load times are often forgotten within the opening seconds of a cut scene, and there are parodies stacked up to the rafters, warped to be child friendly but sure to steal a smile from any watchful parents – and any grown up gamers, naturally.

We spied references to Columbo, The Dark Knight, Goodfellas, Dirty Harry, The Shawshank Redemption and The Matrix to name just a few, and we're sure there are plenty we missed. Then there are winks about actors, history and video games including Street Fighter; we even caught a criminal doing the Thriller dance routine when we scanned him with the GamePad.

In terms of more original comedy, the voice acting – provided by Adam Buxton, Peter Serafinowicz, Josh Robert Thompson and more – is superb. The cast does a great job selling even the silliest of jokes and one-liners, especially when it comes to bumbling sidekick Frank Honey and his unconventional horse-feeding methods. If you've played a LEGO game before you'll already be acquainted with the sound effects – that dangerously-satisfying clink of studs, the rattle of bricks – though the cheesy cop music is new and serves well as a background to the game.