Oscar Collins (Jack MacGowran), an eccentric biologist who lives alone in a London flat, discovers a hole in his wall through which he can spy on his neighbor Penny Lane (Jane Birkin), a model, and her boyfriend (Ian Quarrier), a photographer. Oscar becomes obsessed with Penny, making more holes in the wall so he can peep on her from different angles, and she begins to feature in his dreams and daydreams.
The film is nowadays better known for its soundtrack album, Wonderwall Music, which became George Harrison's first solo album and first official solo Beatles record.note
Wonderwall contains examples of:
- Catapult Nightmare: Not a nightmare, but when Oscar wakes up from a dream about Penny, he sits upright and cries out.
- Compartment Shot: The boyfriend drops by Oscar's apartment to borrow ice, leading to a shot from inside Oscar's refrigerator as the boyfriend grabs chunks of ice.
- Dramatic Drop: When Oscar first meets Penny's boyfriend, he's wearing a wig. When he removes the wig, Oscar drops the bag of apples he just bought.
- Home Nudist: Penny exercises and reads comic books naked.
- Interrupted Suicide: Oscar breaks into Penny's apartment and hides in her wardrobe. While he's there, Penny turns on the gas stove, swallows a number of pills, and lies down in her bed, waiting for death. Oscar turns off the gas, gives her CPR, and runs off to summon help. Penny is taken to the hospital, where she decides to move, because her life needs a change. Freed from his obsession, Oscar puts on a new suit and goes back to work at the lab, where he sees Penny through the microscope.
- Iris Out: Used sometimes at the end of one of Oscar's fantasies.
- Lens Flare: Seen when Oscar spies on a party.
- No Name Given: Penny's boyfriend is referred to only as "the young man."
- The Peeping Tom: Oscar watches Penny even while she's naked or having sex.
- Playing Sick: Oscar's distracted behaviour at work leads his coworker Perkins (Richard Wattis) to ask if he's feeling all right. Oscar seizes the opportunity to take the next few weeks off so he can spend all his time spying on Penny.
- Tantrum Throwing: Irritated at the sitar music coming from Penny's apartment, Oscar throws his alarm clock at her wall. It knocks over a butterfly display, revealing the hole.
