Tim Schafer's latest game tunes up with an in-the-flesh appearance from Jack Black, but it only really starts to play when the character he portrays, Eddie Riggs, makes his entrance. Leather creaking and cigarette flaring in the darkness, it's Eddie - as with many Black characters, he's simultaneously wide-eyed and world weary, lecherous and yet somehow trustworthy - who steals the show, and it's Eddie who holds things together even when it becomes clear that the game, like a band split down the middle by creative differences, seems to want to go in two directions at once for much of the time.
In some ways, Brutal Legend's peculiar ambitions should make for a bewildering muddle, but they don't - and for that you've got Schafer and Black to thank: the experienced, often brilliant designer, and the twitchy, charismatic star, both coming together in the form of Riggs, the eternal backroom boy, the humble, stoical roadie made heroic.
Brutal Legend tells a rather simple story: Eddie Riggs, longing for times when music meant something ("The seventies?" "No, earlier than that. The early seventies"), is injured in a stage accident, and finds himself transported to a fantasy world ripped from the covers of classic metal albums, a world where chrome V-8 engines hang from chains between the columns of druidic temples, where mountains of worryingly unclassifiable skulls peak out from behind statues of vast helms and flaming dragons, and where the terrifying Lord Diviculus - a hot-rod mantis head wedged on an S&M body - has a cruel grip on the land.
The stage is quickly set for a smirking tale of good and evil, told in bursts of thunderous brawling and open-world exploration, and yet Brutal Legend refuses to conform to the template of a typical action-adventure. As a love letter to metal, Schafer's game is focused and all-encompassing, a blur of cameos including Lemmy and Ozzy Osborne, set to a blasting roll-call of classic songs spanning the likes of Motorhead, Black Sabbath and the Scorpions, yet Double Fine's latest wants to explore the potential in blending game genres, too.
As mash-ups go, it's both more disciplined and less imaginative than Psychonauts, Schafer's previous game, which also resisted easy classification. Psychonauts had a mind-hopping structure that let you go anywhere and do anything, flinging you into a Swiftian board-game one moment and a tangle of fetch-quests the next. Brutal Legend restricts itself to just two separate mechanics - those of the RTS and something best described as an adventurous brawler - and it merges the two quite slickly. And yet, inevitably, with such a split focus, the results will bemuse and possibly annoy as many people as they delight.
It's a game of two halves, in other words, and the first could be called Zelda in Leather. There's a pleasant sense of familiarity, despite the comically monstrous setting, with its stone circles, sacrificial pits, and zig-zagging Hell's highways, as you explore the map, taking on missions, learning new moves, and gathering together a band of unlikely heroes to stick it to the forces of darkness.
At times, the borrowings would seem almost shameless (if everyone else wasn't borrowing them too) as you trigger-target baddies, gain a handful of tricks by playing simple tunes at regular stone shrines, and zip about in a flame-splattered Epona stand-in called The Deuce, a fat-tyred roadster which can be upgraded by Ozzy Osbourne himself as the game progresses, until it's a low-riding white-trash Batmobile, tearing across the landscape with gatling guns, homing rockets and flames shooting out of side-mounted exhausts.