Waller makes contact with Dr. Victoria Frias — Mrs. Freeze, a female variant of Mr. Freeze from a Brainiac-invaded world — and enlists her help to stop the invasion on Earth-1 and track down the Flash, whose signal was detected aboard Brainiac's Skull Ship. The squad deploys to Frozen Earth, clears incursions, and escorts Freeze and her cryogenically preserved wife Nora to safety. After defeating the fourth Brainiac — who wields a fusion of Flash and Superman's powers — the squad recovers the Flash uncorrupted. Freeze joins permanently, studying the Flash and inching closer to a cure for Nora, while uncovering unsettling inconsistencies in Brainiac's strategy.