I was interested to find out only a few days before I watched this film that its director, Don Coscarelli, is somewhat notorious for directing bizarre and rather bad (but often cult-following-inducing - notably "Phantasm") horror movies. This one opens with a voice-over by our lead, Bruce Campbell, which includes reference to the oozing pustule on his pecker. You can gauge the level of both the dialogue and the general campiness right there. Campbell's character claims he's Elvis, although he arrived in the rest home he lives in under the name of Sebastian Haff, an Elvis impersonator. Since he broke his hip falling off stage, he needs a walker to get around. He eventually teams up with a black man who claims he's John F. Kennedy (Ossie Davis) to stop a soul-sucking Egyptian mummy (it sucks the souls of the elderly out through their assholes).
Some critics have viewed this as being more about getting old than a horror-comedy, and there's something to that. However you look at it, there's not really a lot of action (and what there is is low speed, as our "heroes" aren't particularly mobile). It's mostly voice-over and dialogue, nearly all weird. The movie has become something of a cult classic, but while I found it kind of perversely fascinating, I'm pretty sure I won't be watching it again.
UPDATE: See also "John Dies at the End," another crazy Coscarelli movie.