"The Constant" is an episode from the popular television series Lost, which aired during its sixth season. The episode focuses on the character Desmond Hume, who experiences time travel and the effects of his unique ability to communicate with his past self. This leads to a deeper exploration of love, fate, and the interconnectedness of events in the series. In "The Constant," Desmond's journey is triggered by a traumatic event, causing him to shift between different points in time. He seeks out Penny Widmore, his love interest, as a way to anchor himself and stabilize his experiences. The episode is notable for its emotional depth and the way it intertwines themes of memory and identity.