Certainly “Lost” is one of the most original shows ever on TV, but it is far from the first series to give us characters “unstuck in time,” as Kurt Vonnegut put it in “Slaughterhouse-Five.” From “Star Trek” and “One Life to Live” to “Quantum Leap” and “The X-Files,” TV writers have played with time travel and invented their own rules regarding chronology and the relationship between the past, the present, and the future.

Are there elements of the “Lost” time-space shakeup that other shows have already toyed with? And will the “Lost” writers ultimately create a time-travel mythology that is markedly different from everything that came before it? Here’s a tour of some TV previous ventures in time-travel.

— Matthew Gilbert, Globe Staff