Strange, don't you think, how the mysteries of time travel continue to fascinate game designers? The theme crops up yet again in this release from the French-based Titus - previously renowned for Crazy Cars II, which was more concerned with travel against time than in it.

You play a knight wandering through different time phases in search of a beautiful princess (you never see her, so for all you know she could have the grace and beauty of Paul Daniels). Along the way you use your trusty sword to wipe out the bad guys.

You can visit five different time phases: Pre-History; a distant time in Versailles (well, it is a French game); present-day New York; the future; and a mystical age.

The enemies you encounter are specific to each time period and to overcome them you must employ certain fighting techniques, learnt through trial and error.

The knight is controlled using joystick combinations. You can make him run, jump, crouch or stamp without holding down the fire button. Pressing the fire button makes him attack.

Depending on how you move the joystick, he uses the sword to thrust forward, swipe or protect himself with the shield. These combinations are logical and it takes little time to learn the techniques.

The game would be just another slay-'em-up if it weren't for a handful of useful amulets. On each level there are one or more of these - but only one of them will be related to the period you're exploring. It's important to pick them all up because they can be used when you shift time.

An amulet appears whenever you destroy the enemy holding it, and they're important because you can't progress through time without them.

The aim on each level is to defeat the merry sorcerer who lives in the castle. One of the biggest problems is how to find your way inside - essential if you want to hack the sorceror into lots of little pieces.

Once the game begins, the only way to move between levels is to find the magic bird and thrust your sword through its heart. Then the time travelling option appears, giving you the chance to deny all rational laws of chronology.

It's the graphics which make Knight Force special. The size of the animated sprites is amazing, although they're not as bright and colourful as they might be.

There aren't many frames of animation in between each movement to keep the action smooth, which is unfortunate because with a little more care we might have seen a graphically superb game.

Sound consists solely of monotonous spot effects each time you use your sword. These are nothing to scream about, though Titus have indicated that they'll be making slight alterations to the effects before release.

There's a lot which stands Knight Force in good stead. The graphics are impressive and well-defined - the sheer size of the main character is appealing. Add to this the amulets, the magic bird and an intriguing time element and you have something fun to play - at least for a while.

Since you can select the initial time period, instead of progressing successively through each level, Knight Force is very exciting to play for the first time. It becomes tedious once the delight in graphics wears off.

The knight can be frustrating if he doesn't respond to the joystick the instant you touch it, especially if you're trying to make split-second accurate assaults on enemies.

If Knight Force had come out two months earlier, the size of the sprites and the gameplay would have made it original; but following so closely on the heels of Altered Beast dampened its impact.

Only for the dedicated slay-'em-up fan.