Pink paper and red ink is all it takes to throw your life into turmoil, as Don Johnston, played by Bill Murray, learns in the nostalgic and witty drama “Broken Flowers.” A mysterious letter arrives in this confirmed bachelor’s mailbox and tells him he has a son by an anonymous woman who claims to have dated him 20 years earlier. Urged on by his neighbor Winston, a detective enthusiast played with appealing earnestness by Jeffrey Wright, Don embarks on a cross-country journey to visit his old flames and find out whether there’s any truth to the letter.

A superb blend of aesthetic minimalism and compelling emotions, it is not surprising that this film received the Grand Prix at this year’s Cannes International Film Festival. The acting is uniformly first-rate; every actor from Murray to “girl on bus” plays his or her role with an attention to detail that contributes to the movie’s emotional power. Kudos to director Jim Jarmusch for eliciting such top-notch performances from all of his actors. He deserves perhaps even higher praise for writing this tightly-woven screenplay, which provides a springboard for all of the performers.

Murray is, of course, the focus of the film—and rightly so. As the apathetic Don, he delivers a performance that is powerfully understated. Audiences are used to seeing this actor play an aging man dealing with his lost youth (see “Rushmore,” “Lost in Translation,” or “The Life Aquatic with Steve Zissou”). “Broken Flowers” allows him to reprise this role.

In a film that depends almost entirely upon the interactions between characters, Murray’s remarkable ability to create a sympathetic character with even the smallest changes of his facial expression improves not only his own performance, but those of his colleagues as well. For example, Murray’s scenes with Wright are particularly enjoyable; the two characters exist in contrast—Murray with his world-weariness and Wright with his infectious zeal, and the result is a humorous and touching relationship. As different as these two characters are, their friendship is based on a strong mutual trust and respect—not to mention a thorough understanding of each other’s idiosyncrasies.

The four women who play Don’s former lovers are equally well-cast. Sharon Stone plays the widowed Laura, a sunny blonde who lives with her adolescent daughter, the aptly named Lolita (Alexis Dziena). Underneath her optimistic facade, Stone adds a sense of vulnerability and loneliness that lends unexpected depth to her character. Tilda Swinton plays Laura’s polar opposite: Penny, the motorcycle chick who lives in a run-down house in the middle of nowhere. Penny’s venomous feelings for Don are nearly palpable, but in spite of her hard exterior, she seems fragile in a way that leaves you wondering exactly what happened between them.

Frances Conroy as Dora, a prim and proper real-estate agent, and Jessica Lange as Carmen, an ambitious lawyer turned “animal communicator,” both play their roles intriguingly, too.

In a box office line-up increasingly filled with explosions and flat, undeveloped characters, “Broken Flowers” presents a welcome change: it is a film about real people with real personal baggage. Set to an eclectic soundtrack, the storyline—especially the ending—is delightfully ambiguous, inviting the audience to mull over this film long after the credits roll by.

—Staff writer Deborah Pan can be reached at dpan@fas.harvard.edu.