Odyssey 5 is a Canadian science fiction series that first ran in 2002 on Showtime in the United States and on SPACE in Canada.

In the United States, the initial run of the series ran for 14 of the 20 episodes, leaving the six remaining episodes unaired for a period of roughly two years. (They aired in 2004 on Showtime as "missing" episodes, which ostensibly included the open-ended series finale.) The show was cancelled despite the fact that the series was one of Showtime's highest rated original series.

The series made a full run of all 20 episodes in the United Kingdom on Sky One and on SciFiUK and in Canada. In 2004, the series aired in Finland on Nelonen and thus could also be seen in Estonia; In 2005, it aired in the Netherlands on NET 5 after midnight. In addition, Odyssey 5 is being or has been aired on RTL Klub in Hungary , and premiered in Australia on the Sci Fi Channel in December 2006. Currently the series airs on Cadena 3 (channel 28) in Mexico, the Sci Fi Channel in the United States, SIC Radical in Portugal and extreme tv in Spain.

Odyssey 5 is the brainchild of Manny Coto, who served as a script-writer and executive producer during the series run. Through his website and in interviews, Coto has expressed his interest in returning to the series at some point, either continuing it or giving it a conclusion.

The series was produced in Toronto, Ontario, Canada.

The astronaut crew of a space shuttle looks on in horror as they witness the violent destruction of the Earth. However, they are given a chance to change humanity's fate when a sympathetic alien sends them five years into the past. Their mission--find out who's responsible for the plot to destroy the planet. Can they deal with their own pasts while saving the world from the mysterious organism known only as "Leviathan?" Written by Anonymous