As “I’m Your Woman” opens, Jean is lounging next to a pool, seemingly carefree, looking like she’s living a life of leisure. In the next scene, the door to her home opens and there’s her husband, Eddie, holding a baby boy. To Jean’s shock, Eddie tells her the child is now hers and hands him over. She’s shocked, but not nearly as much as when Cal, an associate of Eddie’s, shows up at the house a few scenes later and tells her she has to leave with him immediately.

Thus begins an adventure that overturns everything in Jean’s life. Unable to bear a child of her own, she has no experience in handling an infant, particularly when she’s on the run — and doesn’t even understand why. She’s overwhelmed because she’s never really had to take care of herself, but now must figure it out with a baby in tow. Jean can’t even call on friends to help, because revealing the situation to anyone could be hazardous to her health.

What makes “I’m Your Woman” work is that Jean doesn’t know what’s going on, and neither do we. There are no sequences in which we see the forces arrayed against her, the threats she might face, or the truth behind the other characters. We don’t even get much of her backstory. We’re experiencing each situation Jean faces along with her. It reminds me of the way Sam Mendes limited the focus to his two main characters in “1917” (which I reviewed here in January).

Julia Hart, who directed and co-wrote the script with Jordan Horowitz, keeps things tense by focusing not on Jean’s fear, but on the utter loneliness and tedium of her daily existence, interrupted by random moments of action and anxiety. The story could take place anytime, but Hart places it in the 1970s, which gives her a chance to use Aretha Franklin, Bobbie Gentry, and Richie Havens on the soundtrack.

As Jean, Rachel Brosnahan displays more emotional layers than as her best-known character, “The Marvelous Mrs. Maisel.” It’s a subdued yet heady mixture of the stresses of motherhood, the frustration of not even being able to fry an egg properly, and the fear that a stranger could show up at any moment to threaten — or even take — her life.

Hart also gets very good performances out of Arinzé Kene as Cal, Marsha Stephanie Blake as his wife, and the always-reliable Frankie Faison (“The Wire,” “Do The Right Thing”). The outright scene-stealers of “I’m Your Woman” are the incredibly cute twins who play baby Harry — the most photogenic actors I’ve seen on screen in a very, very long time.

I give “I’m Your Woman” an 8 out of 10. It begins streaming on Amazon Prime Video today.

Caveat: while they’re both worth watching, don’t confuse this movie with “I Am Woman,” the Helen Reddy biopic I reviewed last month.