If you've ever had friends ask you over to look at the slides of their trip to Mexico, then you know something of what sitting through "Straight to Hell" is like. Written in three days and shot in three weeks, the movie must have been a toss-away lark -- a chance to laugh it up with pals -- for its director, Alex Cox, who directed "Repo Man" and "Sid and Nancy," but it's a stone drag for the audience.

On paper, the movie sounds like fun. I mean, who wouldn't be intrigued by the prospect of a punk spaghetti western featuring Joe Strummer (a founding member of the Clash), Elvis Costello and the director Jim Jarmusch, with cameos by Dennis Hopper and Grace Jones and music by the Pogues. But don't let the description, or the cast list, fool you.

Filmed in Spain, the movie is set in the sort of dusty western town that served as the backdrop for a lot of Sergio Leone shootouts. The story plots two bands of outlaws against one another. The first is a pathetically inept gang of bandits, led by a surly hombre named Norwood (Sy Richardson). The town is run by the second gang, the MacMahons, a group of caffeine-crazed banditos, whose days, quite literally, are measured out in coffee cups. (Costello is their butler, Hives.)

The action is so gratuitous, and so indifferently presented, that it's impossible to think that Cox ever truly intended it to be seen by anyone outside of the cast and crew and their immediate families. He never attempts anything other than antagonistically unfunny, home-movie-style gags. And most of the exchanges are on the level of the one in which one character, trying to motivate his partner, says to him, "What are you, a MacMahon or a mouse?"

The movie does contain a first, though. In the opening credits, there a listing for Martin Turner as "Sex and Cruelty Consultant." But like most things connected with this film, its promise is never fulfilled. And, as an additional note, I've never seen such a display of bad teeth in my life. That's what the money should have gone toward -- dental work.

Straight to Hell, at the Key, is rated R and contains some suggestive material and violence.