Take the original version of Pac-Man, remove the power pills, the exits from the maze, the on-screen scoring and the hi-score facility, and add instead a few revolving doors.

Now give it a new name and put it on the market as 'a new arcade concoction with a revolutionary new twist'. That's Shifty.

To be fair to Audiogenic, this is a very playable game, but only if you've got a joystick. If you have to use the keyboard then P for up, L for left, ; for right and . down makes playing for any longer than a few minutes a tiresome and frustrating affair.

Add to this annoyance all the omissions mentioned above and you begin to see that unless those revolving doors add something very special then this is going to be one big yawn.

Well, the doors do make a big difference. You can pass through them but the ghosts chasing you can't.

There are three ghosts to start with, and these are soon joined by a fourth. They move faster as the game progresses and are very intelligent.

Despite the absence of power pills and exits, the doors do succeed in adding a new tactical twist that makes Shifty fun to play, even if it is a little unexciting.