The fifth season of the American serial drama television series Lost commenced airing on the ABC network in the United States and on A in Canada in January 2009, and concluded with a two-hour season finale on May 13, 2009. The season continues the stories of the survivors of the fictional crash of Oceanic Airlines Flight 815, after some of them are rescued and those still stranded seemingly disappear to an unknown location and time with the island that they inhabit.