Lloyd is a nice-but-dim taxi driver, who tries to return a suitcase full of money to a beautiful woman passenger. He and his friend Harry journey cross-country to find her in Aspen, where they start to fight for her affections.
As soon as the opening credits inform the audience that Dumb And Dumber was "wrote by The Farelly Brothers", it's obvious that a brain-stretching experience is not on the cards. Cringe not at its apparent terribleness, however, for what follows is a delight: 102 minutes of non-stop, toilet-fixated, pant-wettingly daft humour that has charmed Americans into auditoria in droves and looks set to cause similarly huge bouts of laugh-induced incontinence among UK cinemagoers.
The plot, such as it is, takes road movie form: Lloyd (a mop-topped Carrey), a chauffeur with more room upstairs than the Goodyear blimp, drives the babelicious Mary Swanson (Holly) to the airport, and is instantly smitten. When she leaves her briefcase in the terminal, he retrieves it, and soon he and his equally brain-deprived bud Harry (Daniels) are journeying halfway across America to return the case to the object of his desire.
The scene is thus set for a jokefest of such preposterous proportions that calling it infantile over-estimates the sophistication level by about a squillion miles. Extra-strong laxatives, swaggering homosexual cowboys and urine-quaffing are all trotted out in the name of comedy, while a sub-plot involving a heavy mobster after the briefcase (left at the airport on purpose, naturally) threatens to ruin everything for the air-headed twosome.
Debut director Farelly and his cast romp through proceedings with real gusto and impeccable comic timing, meaning the next jaw-jamming surge of giggles is never more than a moment away, with the normally staid Daniels displaying hitherto untapped comic talent and almost stealing the show from under the nose of his habitually imbecilic co-star. This is by no means the best film ever made, but as an any-night-of-the- week crowd-pleaser it's indisputably the funniest film since Airplane!, and performs further miracles for Carrey's status as one of the world's biggest stars.
Toss those intellectual pretensions out of the window, pack a spare pair of undies and prepare to be reduced to a dribbling, hysterical wreck.