We've been watching the old Poirot TV series, inspired by me getting the book this film is based on last Christmas. More on the series later, perhaps, but it drops in quality in later seasons, when the production company changes.

And in season 12 it does Murder on the Orient Express and it frankly does quite a bad job of it. Not least in the suddenly-Catholic Poirot's struggle with his conscience.

Having him struggling with his conscience over his decision at the end isn't automatically a bad thing. But in the context of the series, it's just not the same character as earlier.

However, we're talking about the 1974 Sidney Lumet film version here. It's no more than OK. If you didn't know the story maybe it would be better, but I'm not sure. It's quite a stellar cast, and most of the individual parts are played well, but in the end it all just comes out as not very good.

Maybe the source material is to blame. Or more likely, the setting. It's like a bottle episode, in that it almost entirely takes place on the train. That maybe doesn't lend itself well to good cinema.