From Dusk Till Dawn was the finest example of how a movie veers completely off the rails to change not only direction but genre. Many have tried but plenty have failed in similar attempts.

Bubba Ho-Tep doesn't turn on a dime like Dawn did, but writer/director Coscarelli throws two ideas together that make the premise of the film funny without even having to watch it.

It's the present day and an elderly Elvis Presley (Campbell) is wasting away in a nursing home, his only friend Jack (Davis), an old black man who claims to be John F Kennedy.

We're never sure if these guys are just demented old men imagining pasts that aren't theirs, but there isn't time for such character nuance while their nursing home is being stalked by an ancient Egyptian mummy, risen from the grave and hungry for the souls of the elderly residents.

Not everything in the film is as distinctive to the theme or premise as you hope, and it leaves a lot unanswered. A less subtle filmmaker would concoct some sci-fi subplot that the spirits of Elvis and JFK were transferred to other men by an Egyptian curse, but Coscarelli's script is only concerned with the crazy idea that the shuffling, mostly impotent former King does battle with a mummy.

Campbell is the most convincing Elvis I've seen on screen, and he rounds out a wild idea well executed.