For a long time it seemed as though creating the near-mythical casual/hardcore crossover game was impossible. Even titles like Nintendo's Super Mario Galaxy, which appear suitable for everyone, are liked far more by the hardcore than your average Brain Training fan. But we hadn't played SEGA's House of the Dead: Overkill, the publisher's new take on the old lightgun series. Somehow this blood-soaked, crude, outrageous Wii game might just appeal as much to Mr Brain Age 40 as it does to Mr Forum Troll.

The lightgun shooter genre has, let's be honest, stagnated a little. The glory days of Virtua Cop and Time Crisis seemed gone for good, leaving us with half-decent Wii versions of some of the classics of the genre. What we didn't see coming was Headstrong and SEGA's superb B-movie take on the long-running House of the Dead series. The games have always been badly acted and somewhat ridiculous, but Overkill makes the most of this quite brilliantly. It's no exaggeration to say we've had more fun with this on-rails shooter than any other Wii release in recent memory.

There's nothing overly complex about the game. Agent G, a slick rookie agent, and Isaac Washington, a completely stereotypical f-bomb dropping, macho American, turn up at a mansion and from then on you're blasting zombies through seven insane levels - presented as short-run movies in the style of the recent Grindhouse double feature from Robert Rodriguez and Quentin Tarantino. Take one moment of Overkill seriously and you'd be completely missing the point. The plot and events that take place in Overkill beggar belief, with a final moment that had a few of us in the office looking agog at the screen, equally in shock and horror.

Washington steals the show from the moment he opens his mouth for the first time, just seconds into the game. It seems incredible that what must be the most profanity-filled game ever has been released on the Wii. This guy is very emotional and says exactly what's on his mind, which is usually a torrent of often hilariously foul language. Combine this with some brilliant evil characters, Varla Guns, the female eye-candy, and Papa Caesar, a somewhat demented crime lord, and you've got a game that only the biggest prude would fail to enjoy.

Two players can blast away together, with up to four supported in the mini-games.

B-movie cool can only carry the game so far though, so thankfully the classic lightgun gameplay has been given a new lease of life here. You're still only pointing and shooting (with a small amount of free-look if you move the cursor to the edge of the screen), but the levels have been made with all the aplomb of SEGA or Namco back in the golden age. The seven levels will take under three hours to blast your way through, but it's a thrilling experience.

New weapons and upgrades can be bought using money earned through your performances, and this adds a small amount of tactics to proceedings. Your default pistol can be upgraded to become a more than handy death dealer, but there's no question that a nicely upgraded shotgun, or better yet an automatic shotgun, does the job a lot better. What you need to consider is that score equals cash at the end of each level, and you get a better score by increasing your combo - the number of kills in a row without missing.

A machine gun might wipe out a room of zombies very easily, but it's also going to miss a lot and prevent you from scoring as many points as you could. On the other hand, while you can continue as many times as you like, each continue costs you half your score on that level up to that point, so maybe a saved life at the cost of a lost combo is worth it. In a great move by Headstrong the completed main campaign isn't the end of things, with a Director's Cut mode opening up that changes the rules slightly. No longer are you able to spam continues (not that most experienced gamers will die too often on their first run through), with a limit of three per level introduced.

The production values really are very good indeed

With this extended, harder game mode, two-player co-op play throughout both campaigns and a handful of mini-games that support up to four players, there really is more here than most lightgun shooter fans could have hoped for. Our favourite mini-game is the brutal Victim Support, in which you must try to help civilians reach exits by shooting the ultra violent zombies trying to clobber them. There's also a survival mode, in which you need to shoot as many zombies as possible until you're dead or the time runs out, and a fairground style target shooting game.

We're surely not alone in our disappointment at the poor production values and presentation seen in many Wii games from third-parties, but it's hard to find fault in Overkill. The detail in the levels, the effects thrown over the screen, the superb lighting and the brilliant aged film grain make this one of the most impressive Wii games we've ever seen - right up there with Nintendo's best work. The soundtrack and voice acting deserve a special mention too, as the two have been handled perfectly. The tunes fit the tone of the game to a tee and regularly raise a smile, while the script and delivery ranges from mildly amusing to the kind of stuff we struggled to believe was actually happening.

Everything isn't all rosy in the world of B-movie zombies though. Although there's no way any Wii owner will be disappointed by the visuals on display here, there is an unfortunate small pause from time to time whenever you blow a limb off a zombie. It's something that becomes less and less of a problem as you play, but when combined with occasional extreme frame rate issues there are clear signs that the console might be being pushed too hard. There are also no online leaderboards - something that is baffling considering the feature appeared in SEGA's Wii port of Ghost Squad.

All the bosses are pretty grotesque.

There's also the issue of how the game plays as a lightgun shooter with an actual gun peripheral. The calibration isn't an issue, with our tests resulting in general performance at least on a par with the aforementioned Ghost Squad, and the aiming reticule can be removed for a more authentic lightgun experience, so that element of the game works very well. The problems arise when, from time to time, certain enemies get up close and you need to shake them off - something that's quite awkward when the Wii Remote is strapped inside a plastic gun. It's not a game breaker for lightgun fans, but we preferred to play using the Wii Remote without the gun shell.

Don't let these problems deter you from picking up House of the Dead: Overkill. As long as you're not offended by strong language and an extreme amount of blood (trust us, there's been nothing like this on any console before) Overkill should be added to your collection as soon as possible. For a lightgun shooter you'll get a great deal of time from the main campaigns, and there are plenty of unlockables and multiplayer modes to keep you coming back. Should you buy House of the Dead: Overkill? Of course you mother fu***ng should!