Until it runs out of steam, Kenneth Branagh’s updated take on Agatha Christie’s classic “Murder on the Orient Express” proves quite an enjoyable ride.

In addition to directing, Branagh cops the showiest role as iconic Belgian sleuth Hercule Poirot, a persnickety man of precision with a wicked sweet tooth and a fabulous mustache. Fastidious to a fault, his daily breakfast is two symmetrical boiled eggs and a piece of toast cut into perfect squares. He’s all about “evidence, order, method,” that is why he’s never met a case he couldn’t crack.

Like Christie’s novel and Sidney Lumet’s 1974 Oscar-winning film adaptation, the new star-studded whodunit is set in 1934 aboard the Orient Express, the luxury train bound from Istanbul to Paris. After a passenger is stabbed to death, Poirot takes center stage, questioning an assortment of colorful characters played by Johnny Depp, Judi Dench, Michelle Pfeiffer, Penelope Cruz, Daisy Ridley, Josh Gad, Leslie Odom Jr., Willem Dafoe, Olivia Colman, Tom Bateman and Lucy Boynton. No one is who they appear to be, and they’re all suspects.

Pfeiffer, enjoying a career resurgence, is a hoot as a slinky blonde widow on the hunt for a new husband. Ridley’s governess squares off nicely with Poirot, especially in one pivotal scene. Bateman is enjoyable as the playboy-ish director of the train. But the rest of the ensemble, from Depp’s shady-looking American on down to Dench’s wealthy princess, barely register. They are merely drawn too thin by screenwriter Michael Green (“Logan,” “Blade Runner 2049”), who allows the stars precious few minutes of screen time. You can feel Branagh’s gracious efforts (we see the back of his head a lot) to give his cast its due, as each member is provided a requisite close-up as Poirot shakes them down.

Like Poirot, Branagh — the director — is immensely attentive to fact and detail, including drawing a robust performance out of Branagh — the actor — playing the quirky detective with a mix of cheeky humor, vim and vigor. The director also adeptly keeps Depp’s scenery-chewing habit in check — no small feat. Branagh has a knack for mood and ambiance, too, vividly creating a lush period drama with an assist from cinematographer Haris Zambarloukos (“Thor”), complete with picture-postcard-perfect vistas of the snowy Alps. You feel transported. Inside, Branagh creates a feeling of claustrophobia and intimacy with a mix of interesting camera angles. And the stars are dressed — as they say — to kill by costume designer Alexandra Byrne, who, for example, outfits Pfeiffer in a form-hugging purple dress, Dench in a snugly fur coat and Boynton in vintage lamé.

Then the story derails, catapulting off a snow-covered mountain of tangled contrivances. Like the locomotive, the story literally falls off the tracks, taking a turn into darker territory involving the effects of trauma and serving of justice. That’s all I’ll say so as not to spoil the ending for those new to Christie’s story.

In spite of the script’s heavy reliance on exposition, the ending cleverly nods to another Christie novel and film, “Death on the Nile.” Should this movie do decent box office, I can smell a sequel, which is OK by me. I’d relish the chance to see Branagh wear Poirot’s fab mustache again.

— Dana Barbuto may be reached at dbarbuto@ledger.com or follow her on Twitter @dbarbuto_Ledger.

“Murder on the Orient Express”
Cast: Kenneth Branagh, Johnny Depp, Judi Dench, Michelle Pfeiffer, Penelope Cruz, Daisy Ridley, Josh Gad, Leslie Odom, Jr., Willem Dafoe.
(PG-13 for violence and thematic elements.)
Grade: B