Robin Wright Penn is the titular character in Rebecca Miller’s domestic drama The Adventures of Pippa Lee, which premiered at TIFF this week. In it, Penn plays the young wife of an aging writer (Alan Arkin) whom she met when he was a middle-aged Lothario and she was a troubled teen deep into sex, drugs and rebellion.

We meet Pippa 20 years on, in a retirement community deep in the suburban heart of Connecticut. Pippa’s life is utterly transformed; she has two grown children, a sick husband and her life is growing smaller. Pippa has morphed from wild child to wife and mother to caretaker but seems too passive to mind.

Familiar old feelings are stirred when the son of a neighbour, played by Keanu Reeves, arrives in the neighbourhood. Eventually they embark on an affair that culminates in a passionate clinch in a truck and was, according to Wright Penn, the toughest she had to shoot.

“Having an orgasm! Thank God it’s short. Right? She’s quick,” she says. “But Rebecca had a good argument. She was like, ‘I really want this to be real-time,’ and I was like, ‘Well, Rebecca!’ And she goes, ‘Remember, it’s been 20 years.’

“Anyways, that was almost impossible to do.”

Wright Penn also revealed she wasn’t Miller’s first choice to play Pippa. Meryl Streep was originally cast but scheduling problems forced her to drop out. Wright Penn’s agent suggested she read for the part and Miller loved her.

Penn is nearly 20 years younger than Streep, and her presence alone adds complexity to the story and raises new questions about Pippa’s marriage.

The actress said she enjoyed working with Miller.

“She thinks like a man, she tells a story like a man, and that’s not being biased against women in any way. But she cuts to the chase and I respond to that in a person.”