From 2014 to 2017, Peter Capaldi starred as Doctor Who’s Twelfth Doctor, the first in a series of new regenerations that the Time Lords gave to Matt Smith’s Eleventh Doctor in “The Time of The Doctor.” Though Capaldi isn’t interest in returning to the franchise, he has no issue talking about his time on the beloved sci-fi series. That includes reflecting on the reason why he kept apologizing to the Doctor Who cast and crew while he was delivering his lines.
While every Doctor is unique in their own ways, one of the things they share in common is frequently delivering complicated exposition and fantastical, kooky sci-fi jargon. It’s entertaining for viewers to listen to, but as Peter Capaldi explained during his appearance on Half the Example, the tradeoff was that there was no way for him to completely memorize all his lines. However, he came up with a cheat to solve this problem, though it’s one that other actors who played The Doctor had come up with on their own, too:
To me, the most important thing was doing the show and that was a lot of work. [It] was wonderful work, but you had to learn all those lines and you literally could not… there wasn't enough time to learn all the lines. So your most basic thing as an actor, which is you learn your lines, you turn up and you deliver them, you couldn't do because you had lots of rewrites by Thursday. By Friday, I no longer had a grasp of the lines. So I had to apologize to people in the morning and say, ‘Look, I don't really… Can we stick them up? Can I stick my lines on the TARDIS scanner?’ Then I discovered that that was a long-standing tradition among Doctors going back to the beginning, of having your script stuck the TARDIS. I don't like that. I'd rather have a grasp of the whole thing.
With The Doctor having traveled across time and space in a big blue box that’s bigger on the inside for millennia, they’ve collected a lot of knowledge about various aliens, historical events, phenomena, etc. We wouldn’t have it any other way with the adventuring Time Lord, but initially Peter Capaldi was self-conscious about how he wasn’t able to memorize all of his dialogue per episode, hence the apologies. At least the TARDIS console was there for him to read over his lines when necessary, though I wonder what he did when he was forgetful during scenes being filmed away from that set.
Peter Capaldi went on to say during the interview that it wasn’t just a matter of delivering his lines on Doctor Who; he also had to put in the work to make sure each of his speeches as the Twelfth Doctor sounded distinctive. As he put it:
It's just that they're substantial. The Doctor's a huge part and he has a lot of big speeches, and you have to find a way to do those speeches that is different. You can't just stand there and present this information because essentially that's what you're doing is presenting this information to get the plot moving. But you can't do that. You have to find a way to illuminate them or to make them more interesting. You have to be an entertainer. You got to come up with ideas and figure that out and practice it. So it takes a while.
Considering what a big Doctor Who fan he was as a child, getting to lead the show was a dream come true for Peter Capaldi. But as happens with all actors who bring The Doctor to life, eventually the time came for him to depart the series, with the actor making his final appearance in the Christmas special “Twice Upon a Time.” Although there have been audio dramas featuring the Twelfth Doctor released since then, he’s voiced by Jacob Dudman in those stories.
Unfortunately, Peter Capaldi’s Doctor Who episodes are currently not available to stream on any platforms in the United States, so you’ll have to purchase your own physical or digital copies. Doctor Who itself will return with a new Christmas special at the end of 2026, with this being the first televised installment in the franchise following the dissolution of the BBC’s partnership with Disney+.