In the wake of a widespread pandemic, the world is a veritable wasteland with so few survivors that upper-crust Abby (Carolyn Seymour) and working-class Jenny (Lucy Fleming) begin to fear they're the only two people left on the planet. As this sci-fi series unfolds, they begin to build up their numbers (with fellow survivors Stephen Tate, June Page, Celia Gregory and Gordon Salkilld) and pour their energies into rebuilding civilization.