Sin and Punishment: Successor of the Skies is about as old school as you can get in these bright-n-shiny, DLC-friendly motion-controlled days. It harks backs to a time when manuals simply said, "run sideways and shoot stuff", to an age when lightning reflexes and a resistance to epilepsy were an essential part of a gamer's toolset. If Sin and Punishment 2 were any more old school, it would be a large dusty building full of kids in oversized blazers, enormous dinner ladies with heaving cleavage, and lonely men with patches on the arms of their faded tweed jackets. As you play, you half expect an over-sized cartoon sausage-on-a-fork to fly past your head (it won't).

But Sin and Punishment 2 isn't just an old-school blaster - or indeed just another on-rails shooter for the Wii; it's a Treasure game, and that fact alone is enough reason to sit up and pay serious heed. You may not know this if you're not a fan of traditional scrolling shooters, but Treasure is pretty much master of the genre. This is the Japanese studio that brought us Gunstar Heroes, Radiant Silvergun, and, obviously, the original Sin and Punishment on the N64. Since the latter was only ever released in Japan (and later on the Virtual Console for everyone else), it's something of a welcome surprise that the big N has decided to give the sequel a global release - particularly given the Wii's casual friendly reputation.

Sin and Punishment 2 stars a young girl called Kachi and a boy named Isa - the son of the two protagonists of the first game. I can't say that I'm familiar with the plot of the N64 original, but I doubt whether you really need this knowledge to appreciate the game's pleasures. Isa and Kachi's spaceship crashes for some reason, and before they've even had time to dig out their insurance forms from the glove compartment, robotic things have climbed into the vessel in an attempt to kill them. Cue an endless carnival of explosions as our intrepid heroes set out to deal with their situation in the only way they know how: by blamming and pew-pew-pewing their enemies into tiny metallic pieces.

On the face of it, this is not a hard game to understand. With the standard Wii Remote and Nunchuck setup, you simply steer your character around the screen with the analogue stick while aiming a reticule at the endless stream of enemies who turn up to ruin your day. Holding the B trigger unleashes a stream of lasers, tapping it produces a melee attack for close encounters, and the A button fires your special attack - which in Isa's case is a massive blue energy sphere that destroys anything nearby. You're free to steer yourself around the screen, and the C button can be used to jump or fly with your jetpack, but your overall progress through the sci-fi environments is dictated by the game. In other words, it's a third-person rail shooter. You clear the screen of nasties, blasting far-off foes and slicing the ones who get close, while ducking and weaving from enemy fire. In addition to taking down mobile enemies, you'll frequently have to deal with wall-mounted lasers and other defences that must be destroyed before you can progress.

I like robo-bikes, I like lizard-things, but which is better? There's only one way to find out...

If all this sounds a bit like Contra, Space Harrier, and any other prehistoric shooter you can think of, you'd be right. If you think this all sounds a bit simple, you'd be right too - but only in terms of the general principles. You'll quickly discover that to get anywhere in Sin and Punishment 2 you'll need to constantly be dodging about using the Z trigger, returning fire all the while, but self-preservation isn't the central aim of the game. No, the point here is to rack up a massive, whopping great score: when you kill successive enemies without taking any hits, you set a combo meter in motion. Take a hit, and your bonus resets. The aim therefore isn't just to kill everyone - it's to kill everyone while showing off your dexterity and foe-juggling skills. Just to hammer this point home, there's going to be an online leaderboard system so you can compare your abilities against the finest twitch-shooters in the world.

Personally, I'm no master when it comes to this kind of breathless, skill-driven shooting, but I can certainly see the appeal on paper. The build of S&P2 at Nintendo's recent European showcase was a stylish little thing, but I'd be lying if I said that I was immediately enthralled: it simply played to me like a hyperactive and unashamedly retro shooter. However, I'm well aware that busy events like these are far from the best place to get as taste for the creeping obsession that develops once a game like this gets its hooks into you. As we've already said, Treasure is an expert when it comes to this kind of score-driven shooter experience; the combo mechanics seem sound, and the action itself is perfectly fun - but this is the kind of title that seems like crack if it sucks you in, and a bit baffling if it doesn't.

Still, it's important to note that the level I played was plucked right from the start - in other words, from the point where the action has barely even got out of bed yet. It'll be the later stages, the bits when the game has actually decided to put up a proper fight, which will seriously demonstrate Sin and Punishment's character. I did get a brief look at someone playing one of the advanced stages, and here Isa appeared to be inside a cavernous tunnel, desperately battling some kind of colossal insect boss - an ugly piece of work that dominated the entire screen. Although brief, this glimpse seemed far more exciting than the comparatively prosaic mini-robots that hassled me as I fled though the metal hallways of my crashed ship. I have absolutely no doubt that the pace will get more hectic after the first level or two, and with any luck Treasure will end up drowning us all in a monsoon of disco laser death. Sometimes less is more, but in the case of twitch-shooters, it's often best to stuff us with action until we burst.

Sin and Punishment: Successor of the Skies is due for released exclusively on the Wii on May 7.