Samuel Anderson Samuel Anderson

Samuel Anderson has no problem being called Mr. Pink. The Doctor Who newbie debuts in the Aug. 30 episode as Coal Hill School math teacher Danny Pink — a nice guy with a possibly not-so-nice background whom Clara (Jenna Coleman) starts dating. But he's much more than just the companion's companion.

After Clara is no longer able to keep her extracurricular activities with the Doctor a secret from Danny, he ends up traversing space and time with the TARDIS crew, joining the illustrious ranks of the Doctor's male companions, which include Jack Harkness (John Barrowman) and Rory Williams (Arthur Darvill).

Not that the Doctor is thrilled. "He wants to make sure Clara is always taken care of," star Peter Capaldi says. "And he's not really sure that Danny's the right person to be doing that because of his past."

But how often does Clara listen to the Doctor? "Danny's so lovable," says Coleman. "He's so laid-back. He's a good counterpart to her uptight, control-freak nature. He brings her back to earth, literally and theoretically."

The 32-year-old Anderson, who starred on Broadway and in London in the Tony-winning play History Boys, had no idea the part extended beyond a single episode. "I thought, 'That's great; that's easy money for me,'" he says. "I'm the specialist at one-off roles."

Anderson found out the truth from Coleman. The pair had already starred together on the U.K. soap Emmerdale (he played a cop, and she was the woman accused of killing one of his colleagues). "I texted Jenna when I got the job, and she texted back, 'A-A-A-A-A-ugh, this is big,'" the actor says. "And I didn't really know what she meant. Then she wrote, 'I'll call you in five minutes.' And when she called, I heard just a big scream and 'You're in the whole story!'"

Doctor Who airs Saturdays at 9/8c on BBC America.

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