SA Jack Harkness

Jack Harkness is a time-traveling human from the 51st century who met the Ninth Doctor and Rose Tyler in the London Blitz. After traveling with the Doctor and becoming an immortal by influence of the Bad Wolf entity, Jack was stranded in 19th century Earth, where he started working for Torchwood Three. Eventually he reunited with the Tenth Doctor and the latter's new companion Martha Jones.

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