The Fosters 1×20 “Metropolis” – As the high school’s Winter Ball approaches, Mariana and Jesus fret about dates and a surprise nomination for Winter Queen raises suspicions. Zac’s mom (guest star Romy Rosemont) shows up at school to talk to Lena. An old friend pays a visit to Callie wanting to make amends, and Brandon feels threatened. But a past mistake could cause Brandon to lose Callie for good. Ana returns with unsettling news for Stef. The episode, titled “Metropolis,” was written by “The Fosters” Executive Producer Joanna Johnson and directed by Martha Mitchell.