Mr Bean is a hopelessly inept security guard at the National Gallery in London and the board of directors wish to fire him. However, the chairman disagrees, so the board decide to send him away to the Grierson art gallery in Los Angeles with the false title of Dr Bean to handle the transfer of the painting, Whistler's Mother. Bean stays with the gallery's curator, David Langley.
Langley soon begins to question the bumbling Dr Bean and his wife Alison daughter Jennifer and son Kevin leave to get away from their hapless guest. Langley finds out that Bean is not really a Doctor at all, and his worst fears are realised when Bean destroys the painting. Langley gets drunk, depressed that he will probably be losing his job.
Langley's family return out of pity and Bean puts his plan of replacing the painting with a poster into action. He breaks into the gallery that night. Bean fools everyone and even impresses the contingent of gathered guests with his strange monologue.
Shortly after the speech, Bean and the rest of the family discover that Jennifer, the Langleys daughter, has been involved in a motorcycle accident. After performing an impromptu successful surgery, when he was mistaken for a doctor, Bean finds himself in Jennifer's room. David Langley begs the supposed doctor for his help, leaving him alone with Jennifer whom he revives from a coma, after accidentally shocking himself with a defibrillator and landing on her. David is surprised to find Jennifer's saviour to be Bean, who asks to stay another week with him.
After spending time with the family, Bean returns home to London. He goes to bed and takes a look at the original painting of the ruined Whistler's Mother which is now hanging in his bedroom.
Bean wins first prize in a raffle at a church fete - a holiday train journey to Cannes.
In France, Bean misses the train towards Cannes due to a vending machine, so he decides to sample some French cuisine at a restaurant while he is waiting. He causes some commotion and then makes his way to the platform. Bean asks a man Emil, who happens to be a film director to record him getting on the train using his camcorder. Bean's bungling manages getting Emils son Stepan stuck on the train with Bean, but without his father, Emil.
Bean and Stepan end up getting kicked off the train. A few adventures later, they hitchhike and get picked up by aspiring actress Sabine in a lime-green mini who is on her way to see herself in a premiere at Cannes. Sabine is under the impression that Stepan is Bean's son, but finds out later that Bean is suspected of kidnapping Stepan, but decides against going to the police as the premiere screening is about to begin.
After Stepan and Bean sneak into the premiere, Sabine and Bean are disappointed to see that her scene has been cut from the film. Bean sneakily plugs his camcorder into the projector, showing his video diary. Sabine, and Bean receive standing ovations and Stepan is finally reunited with his father.
After the screening, Bean leaves the building and emerges onto the beach, encountering other characters from the film. The film then ends with them all miming a musical finale. Bean writes "fin" in the sand with his foot and films it until the camcorder's battery dies.