Barry Season 2 ended on a down note. He is not a reformed killer; he’s a killer-killer, as evidenced by the monastery full of gangsters that he murdered in cold blood out of rage at his handler Fuches.
On top of that, he allows his acting mentor Gene Cousineau to get arrested for the murder of Cousineau’s girlfriend, a murder which Barry himself committed. In the last moments of the episode, Cousineau realizes that his student is indeed a cold-blooded killer, saying, “Oh my god,” before the credits roll.