Mr. Bean, an eccentric caretaker at the British National Gallery in London, finds himself on the verge of losing his job due to his lack of professionalism, often opting to sleep rather than work. However, the Chairman of the board, who has a fondness for Rowan Atkinson, decides against firing him. Instead, the board chooses to send Mr. Bean to Los Angeles, where he must represent the gallery at an important conference regarding their latest acquisition, the illustrious painting “Whistler's Mother,” valued at a staggering $50 million, thanks to the donation from military officer General Newton.
Upon his tumultuous arrival in L.A., chaos ensues when a trick involving his pocket gun inadvertently triggers a terrorist alert at LAX. In an effort to help, David Langley, the curator of the downtown museum, invites Mr. Bean to stay with his family. However, this decision leads to increasing tensions within David's household. His wife, Alison, perceives Mr. Bean as somewhat slow-witted, especially after he accidentally destroys a cherished frame gifted by her mother, prompting her to take the children and leave the house.
At the museum, the director, well aware of the significance of the unveiling, has his reservations about Mr. Bean’s suitability for the task. Yet, David remains steadfast in his support for Bean. An outing to an amusement park results in Bean's arrest for (mis)managing the controls of a ride, which turns dangerously chaotic. The situation takes a turn for the worse when the museum director and his wife come over for dinner, and Bean’s cooking skills lead to a microwave catastrophe with a turkey.
As the unveiling of “Whistler's Mother” approaches, David learns that Bean is neither a doctor nor an art expert, but it’s too late to change course. When left alone with the painting to prepare for his speech, Mr. Bean accidentally gets an ink stain on it and, in a misguided attempt to clean it, erases the face of Whistler’s mother using spandex. In a panic, David hides the marred painting behind a security door, intended for unveiling the next day. After a long night filled with drinks, David discovers his wife, Alison, is back home only to leave again, heartbroken by his drunken state.
Feeling guilty, Mr. Bean breaks into the gallery that night and replaces the damaged painting with a poster he decorates to mimic the original. As the unveiling event progresses, Bean's unpretentious speech is surprisingly well-received. Just when things seem to be going smoothly, David learns that his daughter has been in a motorcycle accident, prompting a frantic rush to the hospital. Mistaken for a doctor, Mr. Bean is swept into the operating room, where he not only saves a wounded police officer but also miraculously brings David's daughter out of her coma.
In a gesture of gratitude, Alison grants Bean an additional week with the family, leading to an unexpected friendship. As David expresses heartfelt thanks for Bean's extraordinary contributions, Mr. Bean returns to London — only to discover the original defaced painting, now an unexpected yet cherished part of his life, adorning his bedroom wall.
