As Ms. Whittaker and her colleagues prepare for their first season of “Doctor Who” to make its BBC America debut on Oct. 7, they are still calibrating how they talk about it. They want to celebrate the show’s inclusivity without chiding the wider genre for a historical lack of representation, and highlight how they have made the series more contemporary and more diverse — behind the camera as well as in front of it — while emphasizing that its fundamental principles haven’t changed.

This is no easy feat for “Doctor Who,” which is accustomed to a certain scrutiny when it replaces its lead actor every few years. The series is also a prominent entertainment property in a field where efforts to diversify are often attacked by a vocal subset of fans.

Despite these challenges, Ms. Whittaker said it was a role she could hardly resist. “There’s no other job like it,” she said. “And I certainly can’t be typecast as it.”

One Sunday in July, Ms. Whittaker was eating breakfast at a hotel here, having made her first visit as a V.I.P. to Comic-Con International the preceding week. This morning, she was daydreaming about returning to the convention center and gawking at other celebrities attending, but, she said: “I’m not allowed. I would need about eight security people.”

A London-based actor who was raised in West Yorkshire, Ms. Whittaker gained early attention for her roles in films like “Venus” (2006), opposite Peter O’Toole, and “Attack the Block” (2011), with John Boyega, before her breakthrough playing the mourning mother of a murder victim in three seasons of “Broadchurch.”