**An overly ambitious film, but still an interesting one.**

Honestly, I expected a little more from this movie. I found it on television, just by chance, but I had already heard about it, I'm not sure for what purpose, but I had the impression that it was a very good film. It's not as good as I expected, as it gets a little lost between politics and police mystery, and that ends up compromising the pace.

It all starts with a drama where an MGB agent named Leo Demidov tries to protect his wife after a political prisoner denounces her as his accomplice. The effort pays off, but it's so obvious that he wanted to protect her that his superiors send him to an industrial city on the outskirts of Ukraine. Meanwhile, he will have to tell a friend that his son died in an alleged train accident, but it is clear that the child was murdered. In the new city where he is posted, Leo discovers many more cases of children in the same situation, deducing that there is a murderer killing children along the railway line. The problem is to convince the Soviet police that these crimes are not exclusive to the capitalist world.

The film has good dialogues and the script is very good, but I felt that it is too ambitious and that it ends up not being able to handle it well. The difficulty in reconciling the two subplots (the criminal on the loose and the protagonist's conflict with the fanatical authorities), both equally powerful and relevant, is palpable. There is another plot point that leaves me with a lot of doubts, and that has to do with how Leo's wife changes radically, from someone passive and without relevance in the story to an active and cooperative figure, central to the following events. If this change, on the one hand, made it possible to put her back at the center of events, it also seems to be an inconsistency. The ending isn't bad, but it's inelegant: the atmosphere of tension and suspense gives way to more action, in absolute contrast to what the film had been doing.

The cast features several well-known actors, starting with Tom Hardy and Noomi Rapace in the lead roles. None of them were bad, they are both quite confidant and the interpretation they bring us is solid and well concepted. Joel Kinnaman is a convincing villain and plays the political fanatic well. Vincent Cassel and Gary Oldman are well-known veterans and pretty safe bets for the most prominent secondary characters. The only negative point I have to make (and I think it's not the actors' fault, but director Espinosa's) is that terrible pseudo-Russian accent that the actors tried to emulate, and which should never have been done. If the director wanted that kind of accent so badly, then he should have looked for Russian or Eastern actors who could speak in English.

Technically, the film relies heavily on cinematography and camera work. They tried as hard as they could for these elements to convey a variety of sensations to the public, from the biting Winter cold to the inhospitable, gray, unfriendly and distrustful atmosphere of Soviet cities during the 1950s. I also really liked the cars, the uniforms, costumes and sets, as there was a good effort at historical reconstruction, in general. The soundtrack does its job, but it doesn't stay in the ear.