In the pages of Doctor Who's comic book adventures, the secret origin behind David Tennant's Tenth Doctor costume was explained, giving the Time Lord a surprising reason for why he sports the look that he does.
In Free Comic Book Day 2015 Doctor Who Special, the Doctor explains that the disheveled costume he usually sports wasn't really a choice of his, but instead was ultimately a malfunction by the TARDIS.
Doctor Who canon is somewhat impossible to crack, as producers and writers of the show have essentially said the time-traveling adventures make it practically impossible to have consistent continuity when it comes to backstories and timelines.
Still, numerous expanded media have tackled additional Doctor Who stories, including introducing a new companion named Gabby Gonzalez, who strictly appeared in the stories from Titan Comics.
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