I typically enjoy Tahar Rahim’s performances, but this romantic drama didn’t offer that much to engage with. The story unfolds in an unusual setting – it’s uncommon to see a nuclear power station used as the backdrop for a romance. That's where his character finds employment, performing some of the repetitive cleaning tasks at the facility. He spends most of his time covered head-to-toe in protective white gear, except when showering or cleansing himself, and develops a friendship with his supervisor "Toni" (Denis Ménochet) while also meeting his girlfriend "Karole" (Léa Seydoux). From this point on, events follow a rather expected course as they begin an affair, hoping to avoid detection from “Toni” or anyone else. Beyond providing a look at their workplace and demonstrating the dangers of the environment – particularly when working within the reactor itself – the rest feels like a passively directed portrayal of two characters who are difficult to connect with, surrounded by minor figures who seem dishonest and deceitful. Maybe the power plant was intended as an allegory for the dynamics of their relationship? There's a train shown at the beginning, which presumably explains the film’s name, but there isn’t really anything particularly impressive about this somber, bleak, and uninspired movie.

Source on TMDB