On October 30, 1969, as Lovell conducts a VIP tour of NASA's Vehicle Assembly Building, his boss Deke Slayton informs him that he and his crew will fly the Apollo 13 mission instead of Apollo 14. Lovell, Ken Mattingly, and Fred Haise train for their new mission. Days before launch, Mattingly is discovered to have been exposed to rubella, and the flight surgeon demands his replacement with Mattingly's backup, Jack Swigert, as a safety precaution. Lovell initially resists breaking up his team, but relents when Slayton threatens to bump his crew to a later mission. As the launch date approaches, Marilyn has a nightmare about her husband's safety, but goes to the Kennedy Space Center the night before launch to see him off.