Maurice (PETER O'TOOLE) is an aged British actor who, when not getting the occasional acting gig, hangs out with his friends, fellow actor Ian (LESLIE PHILLIPS) and Donald (RICHARD GRIFFITHS), talking about the old times as well as the effects of getting old.
For Maurice, he's facing prostate surgery, a procedure that could leave him both incontinent and impotent. He finds the latter bittersweet since he's just met Ian's 19-year-old grandniece Jessie (JODIE WHITTAKER). She's now working as her uncle's housekeeper and neither is happy about that. Nevertheless, and despite her sullen demeanor, Maurice quickly becomes enamored with her.
Of course, he's always been a ladies man, a point that led to his divorce long ago from Valerie (VANESSA REDGRAVE), although the two remain friends. Yet, and despite the massive age difference between them, Maurice finds Jessie alluring, and while she initially finds him to be something of a creepy old man, she eventually befriends him.
As she gives him various peeks at and contact with various parts of her body, their friendship evolves into something more, a development that brings pleasure to both, albeit of different varieties.