Onimusha 3: Demon Siege is deeply stupid, but you will be OK with that. Its stupidity is sweet and enthusiastic. It means well.

The game tells the story of a brave warrior in medieval Japan. His name is Samanosuke. He has a flowing mane of feathered hair that makes him look a bit like Valerie Bertinelli. Despite this considerable handicap, Samanosuke is very, very tough.

One day, when the evil Nobunaga ("King of Demons") floods medieval Japan with hordes and hordes of demons, Samanosuke rises to the challenge. He kills them off by the thousands, swinging his sword with such might and such fury that nothing, not even the most vile supernatural creature, dares challenge him.

At this point a little background is probably a good idea. Demons, on account of their being demons, come ready made with magical powers. Some of them can throw fireballs and bolts of lightning, some of them can give off enchanted poison gas, some of them can materialize out of thin air to launch a surprise attack. You can probably imagine many other magic powers, all of which are standard issue for evil demons. So why the demons of the 16th century should be so fascinated with technology and robotics is a bit of a mystery.

But fascinated they are. The demons have a chief scientist, who goes by the appropriately 16th-century name "Guildenstern." Guildenstern is an old school demon in many respects. He has bony hands with horrifically long fingers. He has a pointy head and a protruding jaw and a cackling laugh. But in a break from demon tradition, he also has an electronic prosthetic eye bolted onto his temple. He is a bit like the book of Revelation and a bit like the Borg from Star Trek. In 16th-century Japan the lines between magic and technology are fuzzy indeed.

Now, Samanosuke. As he is fighting off the demon hordes and making his last stand against the evil Nobunaga in a haunted temple, he is mysteriously caught in a time warp and transported to present day France. At the same time, a French police officer named Jacques Blanc suffers a corresponding inconvenience: he is sent back to medieval Japan. Being unskilled at swordplay and magic he finds himself at a disadvantage, but a friendly genie soon helps him out, teaching him a few tricks and assigning a chirpy little fairy to follow him around.

Got that so far? Japanese warrior goes to France, fights demons. French cop goes to Japan, fights demons, receives advice and encouragement from fairy hovering over shoulder.

It is not easy fitting a story this big into just one video game. That is not to say its producers have not tried their very hardest. They have stuffed the game to the bursting point with video clips, so that after every few minutes of play you get a chance to eat chips and rest your thumbs.

Ordinarily this sort of thing is annoying or irrelevant. Video games are for play, and being forced to watch is rarely as great an idea as it sounds. But Onimusha 3 has such frantic pacing and such aggressive bad guys that you will find yourself glad for the breaks. This is not to say you will enjoy the video clips themselves. They are dumb and filled with demon scientists who experiment with time travel and cackle a lot.

Most of the play experience in Onimusha 3 consists of wading into great seething crowds of demons and hacking at them until they are all dead and you are not. Sometimes you control Jacques, sometimes you control Samanosuke, occasionally you control a French military woman named Michelle. In each case your objective is simple: Get the demons dead.

You also must solve the occasional puzzle, hunting down keys to open locked doors, or sliding tiles around to open a treasure chest. The best of these have you arranging collaborations between the characters, so that something you do in the 16th century lends a hand to your pals in the 21st. It is a neat idea, this. Somebody should develop it into a full-blast time travel game.

But, you protest, this IS a full-blast time travel game! No it is not. It is a slash-the-bad-guys romp, and you can bet your shirt the original plan had the whole game set in medieval Japan. But somebody in business-development sealed a deal with French film star Jean Reno for voice-over work, and there are only so many ways to squeeze a Frenchman in. Full marks to the production team for finding a way.