As her friends anxiously await the outcome of Maggie’s surgery, an unexpected arrival from her mother leads to a tense first meeting with Gary.

Supergirl helps Winn face his greatest fear. After Alex sets out to find evidence against Lex, Brainy must decide between helping his friend or continuing to secretly work for Lex.

Oliver celebrates Thanksgiving with his family but the happy moment is interrupted. Meanwhile, Black Siren returns to wreak havoc on the holiday.