Wedding Day is the 20th episode of season 4 in the animated series.
Mr. Bean is sleeping in his home when his alarm clock goes off. He wakes up and trips over some rope, causing him to fall onto a calendar. It reminds him of Irma's birthday. He prepares by writing up a birthday card and putting it alongside a small-sized cake.
He then drives off to buy some flowers. At a flower stall, he could not afford the price. Spotting a flower bush nearby, he proceeds to take some from it. However, he is chased by a bee, causing him to get in the way of the blue three-wheeled car, in turn causing a wedding car coming from the opposite direction to crash into a mailbox. An upset bride exits the crashed wedding car and cries. Bean decides to help her. He gets her inside his car and drives back to his home.
Having arrived, he parks his car and tells her to wait inside. Inside his apartment, he opens his wardrobe and puts on a blue suit jacket. He steals Mrs. Wicket's bra from her laundry basket to make his car appear as a wedding car. As he is about to go, he remembers about his flowers. He runs back into his home, much to the bride's dismay.
Irma, who happens to have arrived at Bean's doorsteps, sees Bean holding the flowers. Thinking they are for her, she takes them, happy that Bean is being seemingly thoughtful of her. Bean takes them back, and tells her that the flowers are for the bride, who urges Bean to hurry up. Bean gives them to her and drives off. On the assumption that Bean is being unfaithful to her, Irma steals a bike from a woman and angrily pursues him.
He circles a roundabout several times, causing the bride to ask if Bean knows where he is going. He then encounters a traffic jam, which he proceeded to evade by driving on the sidewalk. Irma tiresomely does the same. He encounters a police blockade, which is caused by the recently crashed wedding car. He evades it by driving into a park. While doing so, he nearly hits a couple who are picnicking. Irma, who is still following suit, rides over a banana peel, causing her to crash into a bush. She recovers and continues to pursuit Bean.
He drives through a railway crossing. As she is about to cross it as well, it closes and a fast-moving train passes by. Meanwhile at the church, the groom anxiously waits outside for his bride. As Bean's car nears the church, it breaks down, forcing him and the bride to push it. An exhausted Irma approaches. Bean is pleased by this and takes her stolen bike, much to her frustration.
With the bride sitting in front of the bike, he tiresomely paddles it uphill. As they arrive in the church, they walk in towards the awaiting priest. The priest begins to officiate the wedding, believing that Bean is the groom. Realizing this, he and the bride tries to tell the priest, before Irma and the groom storms in. Irma pulls Bean out of the church and angrily questions him. She sees the bride and the groom behind him getting married. As the bride throws the flowers, she rushes and successfully gets a hold of them.