Rebecca Zlotowski’s “A Private Life” is the rare movie that puts a lilt in one’s step upon exiting the theater. Be warned, however: It is by no means perfect. The picture’s traversal of genres is bumpy, and a smattering of dreamlike sequences skirt the edges of pretension. Still, Ms. Zlotowski has made an entertainment that increases in conviviality as its story rolls along. 

Ms. Zlotowski worked on the screenplay with Anne Berest and Gaëlle Macé. The premise — an innocent party is unexpectedly involved in nefarious doings — is culled directly from the Hitchcock playbook. The film’s later turn to comedy evinces a grounding in the films of Woody Allen, being somewhat reminiscent of the underrated Amazon miniseries, “Crisis in Six Scenes” (2016).

At the center of “A Private Life” is Lillian Steiner (Jodie Foster), an American psychoanalyst in Paris who is having a run of bad luck. One long-standing patient, Pierre Hallan (Noam Morgensztern), shows up at her office unannounced in order to sever relations. The chain-smoking that has bedeviled him for years — a habit that he had engaged the good doctor to help him break — was miraculously cured in a lone session with a hypnotist, Jessica Grangé (Sophie Guillemin). Hallan is peeved at the waste of years and money under the doctor’s care.

More disconcerting is a client who has missed her last three sessions, Paula Cohen-Solal (Virginie Efira). Steiner, being both concerned and frustrated, leaves a voice message on the Cohen-Solal family’s answering service asking about Paula’s whereabouts and informing her that, yes, the missing appointments will need to be paid for. Not soon thereafter, Steiner receives a call from the client’s moody, hard-to-parse daughter, Valérie (Luàna Bajrami), who explains that her mother, Steiner’s patient, has died by her own hand. 

Upon attending the funeral, Steiner is spotted by Paula’s husband, Simon (Mathieu Amalric), and is summarily dressed down by him. Simon is furious, placing the blame for his wife’s death on the psychoanalyst. That note she wrote for antidepressants? It was all but illegible, and the resulting meds were over-prescribed. When Valérie pays a later visit to the doctor’s office, she intimates that Paula may have been murdered. There was, after all, a recent inheritance from a rich aunt. Now that Paula is gone, Simon looks to come into a substantial chunk of change.

Steiner becomes ever more rattled — so much so, that she grasps at straws, including reaching out to her distant, disaffected and dismissive son, Julien (Vincent Lacoste), and a more accommodating ex-husband, Gabriel (a shambolic Daniel Auteuil). When Steiner’s anxiety and doubt escalate, she visits the aforementioned Jessica, of whose methodologies and mysticism she is decidedly skeptical. Still, Steiner succumbs to Jessica’s ministrations only to find herself transported to … Nazi Germany? In a previous life, don’t you know, Steiner was a cellist, Paula her lover, and Julien a member of the German army.

This turn of events elicited groans from members of the audience with which I attended a screening, and I’ll admit to being one of the chorus. But “A Private Life” chugs along all the same, putting these reveries into focus and transforming Ms. Foster and Mr. Auteuil into not only an exemplary comedy team, but a romance for, if not the ages, then certainly for the aged. There’s not a member of the cast who doesn’t pitch in at peak capacity, but special kudos go to Ms. Foster who has rarely seemed as loose, fresh and easy. You’ll fall in love with her character in this surprisingly heartwarming movie.