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For a slow-boat river cruise, and a spluttery sort of movie, “Death on the Nile” covers a lot of territory. It’s a gently but firmly diversified version of Agatha Christie’s whodunit; a mustache origin story; and a film (no spoilers here) in which Armie Hammer takes the role of a weaselly sexual predator, one of many sweaty murder suspects in director and star Kenneth Branagh’s second go-round as Belgian detective Hercule Poirot.

The initial late-2019 release date for “Death on the Nile” was delayed by various factors, notably the early stages of COVID-19, and by accusations of sexual assault and rape that have, for now, derailed Hammer’s career. For a while 20th Century Fox/Disney wasn’t sure how to solve this one. Recast Hammer with someone else, the way Kevin Spacey was replaced by Christopher Plummer in “All the Money in the World”? Recut the picture to de-emphasize the Hammer character’s prominence?

The snag there, of course, is that once you start pulling threads with a whodunit, the entire quilt starts looking sloppy. The latest trailer does a highly strategic job of keeping Hammer’s close-ups and medium shots nonverbal and in the 0.4 to 0.7-second duration range. The film itself, apparently, has been left more or less as it existed prior to the pandemic.

In the 1937-set movie’s early scenes, inside a swank London blues joint, Branagh leans all in on sweaty, beady-eyed Simon Doyle (Hammer), as he sweats up the dance floor, dirty-dancing (after a fashion) with his intended, Lady Jacqueline (Emma Mackey). Seconds later, he’s introduced to his fiance’s friend, the fabulously rich Linnet Ridgeway (Gal Gadot). Poirot eyes this dangerous triangle in the making.

Six months later, Poirot has accepted an invitation to a wedding cruise down the Nile. By this time Doyle and Ridgeway have married, but Lady J turns up with revenge and mad love oozing from every pore. Roughly a third of the way into the picture there’s a gunshot, a corpse and a cumulative spit-ton of expensive but silly-looking computer-generated imagery, making like we’re in Egypt in the ’30s, rather than Morocco (for some exterior shots), a London film studio (for most of it) or an effects lab (for the rest).

“Death on the Nile” takes some story risks that pay off rather well. Screenwriter Michael Green invents an origin tale of Poirot’s mustache, involving the future detective’s terrifying combat experience in the Belgian trenches during World War I. Green and Branagh rethink several characters, thus broadening the multiethnic range of what, as Christie originally wrote, was a blithe colonialist parade of luxury Anglo tourism and pasty-white skin. Sophie Okonedo plays a blues vocalist along for the cruise, accompanied by her niece (Letitia Wright).

The ensemble’s game, but nobody gets much in the way of lighthearted diversion even in the diversionary bits. Behind the camera, Branagh remains a frustratingly indecisive visual thinker. He’s plainly terrified of boring the audience, so he and Green (his collaborator on the 2017 “Murder on the Orient Express”) toss in dumb jolts by way of a cobra strike, or a CGI crocodile. The camera circles, bobs and weaves endlessly while people talk, without much behind the movement besides movement for the hell of it. The S.S. Karnak, i.e., the steamship cruiser, is a beaut. I wish the movie were half as beautiful.

That said, I liked “Death on the Nile” a fair bit more than Branagh’s previous Christie film, partly because it’s a less predictable and schematic narrative to begin with, and partly because Branagh the actor has a way of outfoxing his own pedestrian direction. Branagh’s “Orient Express” also labored under the misfortune of following the 1974 Sidney Lumet version, with Albert Finney et al., a movie I’ve loved since I was 13 and do still.

With “Death on the Nile,” Branagh and company are competing in the collective filmgoing memory with a comparatively minor and erratic picture, the 1978 “Nile” featuring Peter Ustinov as Poirot and a lot of brittle mugging from everyone else. I never thought I’d say this, but: What Branagh’s Christie films need is more mugging, not less. Why let the CGI do all the overacting?

Gal Gadot (with Emma Mackey, left) in the 1937 London-set prelude to “Death on the Nile.”

‘Death on the Nile’ — 2.5 stars

MPAA rating: PG-13 (for violence, some bloody images, and sexual material)

Running time: 2:07

How to watch: In theaters Feb. 10

Michael Phillips is a Tribune critic.

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Twitter @phillipstribune

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