It's been a while since I've expected a Sonic game to be fun.

Since Sonic and Knuckles, I haven't really given the franchise much time, which was convenient, because that's where this game picks up, pretending the whole mess of unplayable 3D titles with too many characters never happened.

Dimps and Sonic Team have really gone back to basics this time. The game opens with the SEGA logo showing up and announcing itself in just the way you remember it. The title screen that follows is almost identical to those used in the early games. The music, too, is repetitive in that familiar Sonic way.

When you start playing the game, you're looking at the original 2D side-scrolling gameplay. Using the left analog stick or d-pad sees Sonic start walking, then speed up, then start running, with all the smooth fluidity of a blue hedgehog in his prime. Pressing X or O will make him jump, and pressing the button again does a homing attack - making Sonic either dash forwards or directly at the nearest enemy, depending whether the lock-on indicator is displayed.

A spin dash can also be triggered on the ground by pulling the stick down while pressing one of the jump buttons. Doing this makes Sonic spin in place as long as you keep the stick angled down, allowing him to speed forwards and blast through enemies when released. When you run into an enemy without using your spin dash, or when you hit a spike trap, Sonic falls over and drops his rings, just like he used to.

When you hit something dangerous without any rings on hand, you lose a life and restart at the last checkpoint you activated. And you will run into traps you didn't see coming, just like you used to. It's old-school Sonic all the way down to the "learn where hazards are" gameplay. Many enemies and traps are impossible to get past unless you know what's ahead before it's visible. Especially the chameleons in the first area, which appear on walls when you get close, and shoot at you.

Even slow-and-steady won't give you time to react to some hazards.

If you manage to finish a level with more than 50 rings, there's a giant ring which lets you unlock a secret level (but only if you jump through it in time). These, like the rest of the game, are throwbacks to the originals, with Sonic spinning in the centre of the screen and slowly falling, while the left and right controls rotate the stage in the opposite direction to what intuitive controls would do. The object of these stages is to reach the Chaos Emerald at the end. Most walls allow you to bounce gently, but there are occasional bounce pads which send you flying on contact, and some barriers which you need to hit a certain number of times to open, or which only allow you through once you have a certain number of rings. You can be dropped back into normal gameplay if you run out of time, or hit an exit pad on the wall.

There are also the obligatory boss levels, where Dr Eggman (I still think of him as Robotnik) is in some slow-moving contraption he's built to try and take on the super-speed hedgehog. Because, as usual for evil geniuses, he's not that smart.

Once you've defeated him, his machine crashes and burns.. again. Some of these stages can get rather frustrating, I had to repeat the casino level several times before I got lucky and wedged myself in a corner where I was bouncing back and forth between the boss robot and a flashing pinball wall which fired me straight back for continuous damage. Every run before the victory was a long and hard-fought battle, and winning like that felt anticlimactic, but again, it reclaims the old Sonic feel by doing this.

The graphics are about the only concession to modernity, and are at least as impressive as the other current-gen Sonic titles. This game looks exactly the way old-school Sonic fans would imagine a modern remake of the old titles. Unlike the gameplay, the graphics are 3D, and there are a few moments where the game shows this fact off to great effect. The colour schemes and design of the levels are distinctive, with each 3-part stage (4-part if you count boss fights) having its own unique visual style, all revolving around bright, vibrant colours, reminiscent of the 16-bit origins of the franchise without being restrained by them.

Really, if you liked the old Sonic titles, the only criticism I can give is that it hasn't brought anything new to the table. And for almost $25, that's no small flaw. If you really love the old Sonic games, and want to see them with a current-gen facelift, Sonic 4 is worth the asking price. If you don't know the Sonic of old, I can't give the game such a strong recommendation.

What I can say is that I had a blast with it, and those who remember where Sonic came from probably will too.