There’s a good movie somewhere in “The Good Mother,” a showcase for the always-interesting Hilary Swank, but unfortunately co-writer and director Miles Joris-Peyrafitte can’t find it.

Swank, the two-time Oscar winner, is Marissa Bennings, an Albany, N.Y., newspaper reporter and functioning alcoholic who is pulled out of a morning news meeting to be told her drug dealer son, Michael, has been killed. The cop who tells her this news is Toby (Jack Reynor of“Midsommar,”Prime Video’s“The Peripheral”), her other son.

At Michael’s funeral, Marissa finds out his junkie girlfriend Paige (Olivia Cooke of“Thoroughbreds,”HBO’s“House of the Dragon”) is pregnant, and reluctantly takes her in. Paige has been clean and sober since she learned she was pregnant, and hopes to stay that way. Together, they investigate Michael’s killing, and the key might be Michael’s best friend and fellow dealer, Ducky (Hopper Penn, son of actorsSean PennandRobin Wright).

The problem with the film, however, is that for a lot of the time, Marissa and Paige aren’t doing much sleuthing. For long stretches, “The Good Mother” appears to be a character study of Marissa, a widow who now has to grieve one more time. At other times, it is a tale of redemption and reconciliation, with perhaps Paige becoming something of a surrogate daughter. The thriller aspect is lost — and then it reappears every so often, awkwardly.

Of course, it is possible to make both a thriller and character study at the same time (Robert Altman’s 1973 take on Philip Marlowe in “The Long Goodbye” is a textbook example), and Swank, who is quite good, makes Marissa’s flawed heroine someone to root for.

At one point, her editor (veteran Broadway actor and singerNorm Lewis) tells Marissa, “You’re my best writer, but for some reason, you refuse to write.”

“The Good Mother” works best when Marissa is trying to solve that dilemma. One of the strongest scenes is when Marissa meets a woman (Karen Aldridge) at a self-help meeting whose daughter died of a fentanyl overdose. They seem to make a connection, but that lasts about three scenes, and then the woman disappears from the movie.

All that’s to say that it seems Joris-Peyrafitte can’t decide what film he is making, and as a result we’re left with a jumbled mess with a slapped together resolution that will satisfy no one.

Reach G. Allen Johnson:ajohnson@sfchronicle.com