‘The Rhythm Section’ – a forgettable movie with inept plotting

A scene from "The Rhythm Section"
By Eleanor Ringel Cater
What’s there to say about a movie that slips out of your head before you slide out of the parking lot?
Not much, I’m afraid.
Not much good, that is.
“The Rhythm Section,” alas, is that movie.
Sort of a down-market “La Femme Nikita,” “The Rhythm Section” stars Blake Lively and an assortment of wigs (drug-addict dirty blond, business-like brunette and flame-tressed seductress). Before she became a spy, Stephanie Patrick (Lively) was a hooker with a heroin habit. Before that, apparently, she was a smiling, happy middle-class person from a smiling, happy middle-class family.
And there’s the rub. Said family was killed in a suspicious plane crash, leading to the prostitute/druggie phase which leads, in turn, to her decision to become a trained assassin. Once, that is, she finds out that her loved ones were probably collateral damage in a terrorist attack.
In the film’s far better first half, she travels to Scotland to learn the tricks of the trade with an ex-M16 agent named Boyd (Jude Law). Initially reluctant, he puts her through a tough-love drill that includes everything from icy dips in a freezing river to Wild West-style target practice.
Then he sends her off on her own, into a second half filled with good actors (Sterling K. Brown, for one) and inept plotting. Stephanie gets herself into dicey situations that never engage us. True, we’d rather not see her killed – she is, after all, the star – but beyond that, it’s difficult to feel much connection with our protagonist or her movie.
Incidentally, I scribbled down the film’s explanation of the title: “Your heart is the drum, your breathing is the bass. Keep the rhythm section tight and the rest of the song plays itself.”
Somebody, anybody, please explain.