Jimmy Stewart stars as Elwood P. Dowd, a man who's friends with a 6 foot invisible rabbit in this light-hearted look at the victims of mental health facilities who suffer from acute psychosis. Dowd shares his home with (besides the giant rabbit) a nervous older sister and her equally unbalanced, man-hungry 20-something daughter. Dowd has inherited a great fortune you see, and like all others who inherit large sums of money, he seems to have a screw loose. His sister, while somewhat crazy (she only sees the rabbit SOME of the time), still feels it's her brother who's holding back their climb up the social ladder, and because of this, she decides she must commit her brother to the local mental institution. From this point, the hijinks ensue. It's implied throughout the movie that the giant rabbit might actually exist, and is something called a "pooka". In fact, I may have to quote wikipedia here: "There is a humorous scene in which Mr. Wilson, the asylum orderly, reads the definition of pooka in the encyclopedia: 'Pooka. From old Celtic mythology. A fairy spirit in animal form. Always very large. The pooka appears here and there, now and then, to this one and that one at his own caprice. A wise but mischievous creature. Very fond of rum-pots, crackpots, and how are you, Mr. Wilson?' This provides the notion that Harvey is real." The thing that separates Harvey from other mentally disturbed pictures, like say, "12 Monkeys", is that Elwood P. Dowd is such an affable character. While his sister is running around throwing hysterical fits over the tiniest thing, Elwood spends his time hanging out in the local bars, introducing himself to strangers and inviting them over for dinner. It's his goofy charm that carries the weight of the movie. When his sister takes him for a drive up to the sanitarium, he goes along just as affably as you please. When Mr Wilson gets rough and drags him up to the scrub-down area, he's still trying to introduce himself to everyone and invite them over for dinner as he's being pushed along. To quote Dowd: "I always have a wonderful time, wherever I am, whomever I'm with". It's a wondefully well-written script, delivered in memorable performances.