A click, a warble of machinery, a mild retro fuzzying of colours and textures - and in one of this year's crazier spectacles, a swarm of household objects arcs slowly into view. There's time to gawp, as chunky cartoon furniture pinwheels across the room at a glacial pace, but we don't. We leap, instead, to the flank of a lazily spinning safe, reorient ourselves quickly and leap for an armchair, working our way towards the exit door high up the opposite wall.
This is Quantum Conundrum at its best - a first-person puzzle adventure which percolates a library of mad science concepts through a carefully judged series of scenarios, somehow ensuring that you grasp what's necessary at any given moment, however deranged the notions in play. And it's also Quantum Conundrum at its worst, as we misjudge the final jump and plummet into the abyss. Airtight's debut XBLA effort is more than a cutesy clone of lead designer Kim Swift's prior work, reaching beyond Portal's dimension-folding mechanics to powers that up-end gravity, curdle the flow of time, transform iron to cotton wool and vice versa. Unfortunately, these tricks also create a frustrating dependency on precision and quick reflexes, tarnishing the sheen of what is otherwise the best, most substantial Xbox Live Arcade brain-teaser in ages.
The narrative reads back like a sanitised version of Portal's lab rat satire, but is conducted with enough gusto to prevent the game's dozens of puzzle chambers feeling lifeless. You play the nephew of a crackpot hermit, Professor Fitz Quadwrangle, who's gone and trapped himself in an alternate reality and is present throughout as a disembodied, all-seeing, all-condescending voice, prodding you around his mansion with a bombardment of tips, jibes and Nickelodeon anecdotes. Early on he equips you with the Inter-Dimensional Shift Device, a glove-mounted gadget which will eventually let you flick between four dimensions, altering the material properties of your surroundings as you go.
The first of these is the Fluffy Dimension, which turns the world mattress-coloured and reduces everything to the weight of a paper cup, allowing you to move heavy furniture and safeboxes around to (for instance) trigger pressure-operated switches (the use of locked safes as keys to puzzles is a joke Swift and her cohorts rarely tire of). The Heavy Dimension has the opposite effect, multiplying object mass and also rendering them usefully resistant to laser beams. The brilliant Slow dimension freezes tumbling objects into navigable platforms, while the Reverse Gravity dimension lets you jostle chunks of scenery around by toggling the bumper to jiggle the Earth's pull.
Encompassing over five hours of playtime, the mansion has an entrance hall, three wings and a final area, and the nature of the challenges ebbs and flows accordingly. On entering each section, you'll run into a few lighter, faster puzzles where the play of realities is mostly beyond your direction - palette cleansers that also acquaint you with new sets of mechanics, like the fans which propel Fluffy objects out of place. Eventually, you'll discover batteries that enable manual control of the dimension-switching, and the game starts to test you with situations that require you use two or more dimensions in tandem - throwing a safe, slowing time in order to use it as a moving platform, leaping to solid ground and finally turning to snatch the object out of the air.
The complexity ramps up steadily, but the pedagogy is perfectly pitched to ensure that nothing overwhelms. Immense consideration has been given to what's in view when you enter each chamber, and punning title cards hint at the solution. Though a touch generic, the game's warm painterly colour scheme makes it easy to distinguish the ingredients of each puzzle, and however labyrinthine they may appear at first, the layouts have an underlying spiral logic which keeps you pointed in the right direction.