Its a film which posits that Elvis is not dead, he got too angry with fame and swapped places with an Elvis impersonator. Now he is old, his hips keep popping and he has cancer on his penis. He's in a nice but definitely no-frills retirement home. Also in the home is JFK, he survived the assassination attempt, had sawdust put in his skull to fill out some of the brains, and had his skin permenantly dyed black.
Then a mummy, which had been en-route to a museum until the lorry crashed into a lake, wakes up and starts sucking the souls of the defenceless old people. It's up to Elvis and JFK to save the day.
Actually it's a surprisingly sweet and touching film.
Bruce Campbell plays Elvis and Ossie Davis is JFK