10. “Inside Llewyn Davis” (2013)
Who Mulligan plays: Jean Berkey, a singer in the ’60s folk scene. Although she’s married and makes music to Jim (Justin Timberlake), Jean has an affair with the titular struggling artist Llewyn Davis (Oscar Isaac), which causes complications when she gets pregnant and needs an abortion.
Why she’s great: Joel and Ethan Coen’s fantastic portrait of artistic struggles is too wrapped up in Isaac’s self-destructive musician’s perspective to give the supporting cast much in the way of screentime. Even though Jean is one of the more prominent figures in Llewyn’s life, it’s one of Mulligan’s smaller roles that isn’t a literal cameo. But she still leaves an indelible impression as the abrasive, foul-mouthed Jean, filling the role with enough personality and venom that she becomes almost as complicated to like as the lead hero. Her ragged, testy chemistry with Isaac complements the character’s difficult dynamic well, making it clear that this bond is as important to them as it is constantly strained.