In the episode, Central Intelligence Agency agent Rex Matheson (Mekhi Phifer) takes Torchwood team members Jack Harkness (John Barrowman), who is the only mortal human, and Gwen Cooper (Eve Myles) on a plane to the United States.
During the flight, a traitor in the CIA (Dichen Lachman) poisons Jack with arsenic and Rex, helped by Dr. Vera Juarez (Arlene Tur), find an antidote using only items found on the plane.
Rex has Jack and Gwen board a plane headed to Washington, D.C., with fellow CIA agent Lyn Peterfield escorting them.
With fears that supplies will dwindle as the undying grows, Vera suggests that hospitals need more painkillers to handle this situation.
When Director Brian Friedkin suspects Esther and Rex may know too much about Torchwood, he has their security clearances deleted, frames them as spies working for China and orders Lyn to kill Jack with an arsenic pill.
With the help of her fellow doctors at the medical conference and the air stewards on their plane, Rex and Gwen successfully create an antidote and administer it to Jack.
No one has yet suggested mandatory birth control, but we do see discussions about the fact that the entire medical industry would have to change from a life-saving position to one that’s more about pain management.