Lt. Sharon Valerii wakes up soaking wet in the tool room with an explosive charge in her duffel bag. Shortly afterward, a mysterious explosion destroys all the port-side water tanks on Galactica, creating a crisis for the entire fleet. Sharon can't remember a thing, but all the evidence points to her as a saboteur. She confesses her concern to Chief Tyrol, but he can't believe she's responsible.
As water riots erupt, Commander Adama and President Roslin struggle to contain the crisis, putting all the ships on limited rations and assigning Baltar the job of rooting out any Cylons who may have infiltrated the crew.
Meanwhile, on Cylon-occupied Caprica, another avatar of Sharon struggles to save Helo, her stranded Raptor crewmate.
