what did bree see on evans computer

In Tell Me Lies season 3, episode 7, Bree is on Evan’s computer looking through old photos when she notices a picture that changes everything.

In that photo, she sees Evan talking to Lucy at a party, and Evan’s hand is clearly on Lucy’s hip. This is how Bree realizes that this was the night Evan cheated on her, which sets up the tense moment where she then grabs his phone at the end of the scene, clearly ready to dig further into what else he might be hiding.