“Murder on the Orient Express” is definitely not a great movie: It relies too heavily on CGI-generated sweeping landscapes, its attempt to grapple with racism in a period context unravel as the plot proceeds, it has tonal inconsistencies, and post-“Pirates of the Caribbean” Johnny Depp’s presence subtlety goes missing in a disappearance worthy of the interventions of Agatha Christie’s great creation Hercule Poirot. But even though I noticed these flaws while I was watching the movie, they weren’t enough to overwhelm its better qualities. “Murder on the Orient Express” is, among other things, an argument in favor of purely competent moviemaking, among them carefully-framed, delicious-looking shots, some outstanding costuming, and most of all, a solid set of performances.

Prominent among those is Branagh’s turn as Poirot, which anchors the movie’s fundamental sense of decency. Branagh has fun with Poirot’s fussier mannerisms, from his obsession with the size of his morning eggs to the magnificently ridiculous contraption he uses to preserve his mustache while he sleeps. But he also does a delicate job of portraying Poirot as torn between a sense of profound duty born out of his talent and his eccentricities, and the rest he desperately needs.

“I can only see the world as it should be,” Poirot explains early in the movie. “When it is not, the imperfection stands out.” As a director, Branagh wisely resists the urge to retroactively diagnose Poirot with some sort of autism spectrum disorder, though “Murder on the Orient Express” could have made that leap. Instead, the movie depicts Poirot as someone who finds crime and injustice almost physically intolerable. The film’s most important insight is that the most interesting thing to do with that concept is not to make Poirot merely a genius of detection, but to force him to employ his skills in a situation where justice is not neatly achievable in a fashion that both Poirot and the audience would find most comforting. At the end of “Murder on the Orient Express,” the murder is solved in the sense that we know whodunit, but the larger moral dilemmas are resolved in only the most unsettling fashion. For a $55 million movie, its best special effect is its general air of melancholy.

To this end, Branagh is aided by a series of very able performances from a group of actors who have a meaty task before them: playing characters who begin as stock figures, and without exception, turn out to be more interesting than the stereotypes they embody.

Miss Mary Debenham seems like a starchy governess before Daisy Ridley sets out to immediately reveal her steel. Pilar Estravados comes across as a rigid missionary until Penelope Cruz sets about revealing the extent to which that rigidity is a survival mechanism. Willem Dafoe, whose face so often leads him to play moral or literal gargoyles, gets a chance to soften up Gerhard Hardman, a professor and a nasty piece of work. And though I dare not say more about Michelle Pfeiffer’s work as the husband-hunter Caroline Hubbard for fear of revealing (or reminding you of) the plot’s resolution*, let it suffice for me to say that she gives a performance that makes me curse the years she wasn’t on my screen as at least partially wasted.

Maybe I’ve lowered the bar too far, and I should be asking for more than a picture to be reasonably handsome and morally engaged in a way that’s enhanced by a set of fine performances by generally strong performers. But 2017 has been a bad year, movie-going and otherwise, and in its relatively modest way, “Murder on the Orient Express” felt like a bit of a reset, a reminder of what a well-constructed picture can make me feel without resorting to yet another tiresome battle scene or grimy, limit-pushing shock. Sometimes, measuring the distance between the world as it should be and the world as it actually is turns out to be observation enough.

*Longtime readers know that I, personally, almost never give a fig about knowing plot details of a story ahead of time, but “Murder on the Orient Express,” especially as interpreted here, is one of those things that’s best come to as cold as possible. I know I enjoyed it more for having forgotten the ending and remembering it only part of the way through.