10 Sci-Fi TV Shows That Wasted Incredible Characters

Doctor Who's 2005 revival made a lot of changes to the sci-fi powerhouse. After meeting the Ninth Doctor and his new companion, Rose, we're soon introduced to the dashing, charismatic Captain Jack Harkness.

Played by the effortlessly cool John Barrowman, Captain Jack quickly became a fan favourite, slotting perfectly into the show's new dynamic as a series regular.

After the Ninth Doctor's departure and the Tenth's arrival, Captain Jack began to make fewer appearances. At this point, he had been established as immortal, which was an occasional plot-point, but the implied lower stakes perhaps put the show's writers off of using Jack too regularly.

Then came the reveal that Jack aged over billions of years to become the giant, mysterious head-in-a-jar the Face of Boe, and suddenly Jack was all but written out of the show.

The reason, of course, is that he was given a spin-off, but given his chemistry with the Doctor, his competence and his immortality, it was both frustrating and disappointing for fans that he wasn't featured more heavily.