This is a movie from the biggest spy breach in US history. The genre of this movie I have seen before, one young guy that is set to work "undercover" to get friendly and trusted by someone else in order to achieve the desired goal. However this movie is very different in the way that it doesn’t ask why - it even says in the end of the movie: There is no reason to ask why? - But you know what, I want to know why. I see a movie with a spy that is obviously a psychopath and no references to why it is so.
It is not a thriller, because all scenes that are meant to wake the thrilling sensation are all in avail. It is moreover some kind of drama film, and since we are presented to a super psychopath spy as well without knowing why, this movie is more about the cost of working for FBI and the willingness to pay that cost. This theme is however meant to be a side theme, like seen in many other movies.
Is it worth to see this movie? If you want to learn about the biggest spy in US history: no. If you like to see a drama movie: yes, maybe.