But once it's in motion it begins to perform gratifyingly... and it definitely gets us to our desired destination.
Based on a classic mystery novel by Agatha Christie, the story has already been adapted into an excellent film back in 1974, directed by Sidney Lumet, with a script by Paul Dehn, the backbone of the first Planet of the Apes franchise, and Anthony Shaffer, who wrote Sleuth.
This version is directed by Kenneth Branagh (who also plays Christie's hero, the detective Hercules Poirot) and has a script by Michael Green.
Green is an interesting writer, with extensive television experience and some recent high profile feature film credits. He was involved in both the terrible Alien: Covenant and the wonderful Blade Runner 2049.
Michael Green has made a number of changes to the original. The new movie begins with Poirot swiftly solving a high profile case — a sort of mystery in miniature — in Jerusalem. This isn't a bad idea, setting up the detective hero and his shtick at the outset of the film. I just felt it was done rather clumsily.
And Poirot has been given a trusty cane which he wields for numerous purposes. This heightens his resemblance to a comic book super hero with his gimmick and a set of "super powers" which are set up by that mini story at the beginning.
He's also been given an obsession with symmetry which seems utterly irrelevant until the end of the film when the detective has to decide — in a surprisingly moving scene — if he can allow the scales of justice to tilt to one side.
Green's script is often funny — there's a startling early scene with a cheerfully unabashed prostitute and her client — and he has the good sense not to mess too much with the essential Agatha Christie plot, which is very clever and which I have no intention of spoiling by revealing here.
The movie is produced, but not directed, by Ridley Scott, and although I am often harsh in my judgements on Scott, there is no question about his astonishing visual ability as a film maker. I rather missed his presence at the helm on several occasions here — I doubt he would have sanctioned the cheesy and unconvincing CGI (for example, of period Istanbul).
And Branagh isn't great at staging action. There were some incidents when I couldn't even tell what was going on, and one long tracking shot just didn't work for me (we're outside the train looking in, so having the dialogue from inside play over the scene felt rather odd).
But where Branagh really scores is as a magnificent director of actors, and he has assembled a superb cast of them here. They're not the big names, either. Josh Gad plays a flunky to Johnny Depp's gangster. I'd never heard of Gad before, but he has a monologue in the movie which is so superbly performed that it should be screened in every acting school in the world.
Daisy Ridley impresses, as well, showing how far her range extends beyond the Star Wars franchise (in which she was great, incidentally). But again I was knocked out by a less well known name — Lucy Boynton. She plays a drug addicted countess here and she only has one brief monologue, but it's searingly vivid and convincing.
An amazing cast, and Branagh has drawn the best out of them. His Poirot moustache is truly horrid, but then that's sort of essential for the character. And Green's script cleverly makes reference to other classic Christie Poirot cases. At the end, the detective sets off to begin the next investigation...
And for once the prospect of a sequel is entirely welcome. Here's hoping Branagh and Green will have Hercules Poirot back on our screens soon.
(Image credits: No shortage of suspects at Imp Awards.)