When "Doctor Who" Season 10 airs later this year, it will conclude the tenure of showrunner Steven Moffat as well as current Doctor Peter Capaldi, who recently confirmed his long-rumored departure. But while fans will miss them, these exits were to be expected, as "Doctor Who" will pass hands to new showrunner Chris Chibnall in 2018.

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With the prospect of casting a new Doctor, the age-old question resurfaces: Why does the Doctor have to be male?

There is precedent for a female Time Lord, as the Master has been portrayed by both male and female actors, like John Simm and Michelle Gomez. If Chibnall does decide to look outside the traditionally male-cast box for his new Doctor, he should search no further than "Agent Carter's" Hayley Atwell.

No stranger to British television, Atwell has starred in numerous U.K. productions, including "Mansfield Park," in which she appeared with one-time "Doctor Who" companion Billie Piper. While Atwell has never guest starred on the "Doctor Who" television series, she did lend her voice to four "Doctor Who" radio dramas, from 2006 to 2013. Atwell is also familiar with devoted followings, with her turn as Marvel's Peggy Carter positioning her squarely as a female role model to fans of the comics, TV series and films alike.

Her introduction to the Marvel Cinematic Universe in "Captain America: The First Avenger" proved decisively that Atwell is no mere companion; she'ss a leading lady who could handle herself alongside heroes like Captain America. After "The First Avenger," Peggy Carter was positioned like Agent Coulson and Nick Fury, showing up in "Captain America: The Winter Soldier," "Ant-Man" and "Agents of S.H.I.E.L.D." Peggy was hailed as one of the founders of S.H.I.E.L.D., a journey explored in seasons one and two of "Agent Carter." But when that series was canceled in 2016, fans mourned the loss of their favorite character and even launched a "Renew Agent Carter" petition that garnered more than 100,000 signatures.

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With Peggy's story seemingly concluded, now is the perfect time for Atwell to join a new fan-favorite project. Atwell's schedule is open; her follow-up project to "Agent Carter," "Conviction," was quickly canceled, leaving her perfectly poised to join "Doctor Who" as its first female Doctor. In terms of companions, she could either go the traditional route, with a female sidekick, or bring on a male one. Her partnership with James D'Arcy's Edwin Jarvis on "Agent Carter" was delightful; in fact, Jarvis practically was Peggy's companion on that show.

More than a dozen websites immediately nominated Atwell for the new Doctor's role -- not a surprise, given her once stating she'd love to play the part. Comic book artists have also shown their interest in Atwell by drawing her as the Doctor, with "Green Arrow" artist Stephen Byrne posted the following artwork early Tuesday morning.

Who's that girl. pic.twitter.com/eYrcWam5GU

— Art of Stephen Byrne (@StephenByrne86) January 31, 2017

Atwell is an amazing actress, demonstrating depth of character, warmth, humility and smarts as Peggy Carter. She can play both the comedic actress and the series' action star. From her heartbreaking role as Martha on "Black Mirror" to her turn as the fierce mistress in "The Dutchess," Atwell has proved the extent of her range as an actor.

Of course, the main reason Atwell should be considered for the next Doctor is because it really is time to change up the "Doctor Who" formula. The Doctor has been a white male for more than 50 years, and now is the perfect time to switch that up and introduce something different. Chibnall could cast a person of color, he could cast a woman, he could cast anyone who doesn't fit the stereotypical box of "Doctor Who."

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Atwell would be the perfect person to step into this new territory because she is already loved by so many fans. She is well known in both the United Kingdom and the United States, so her appearance on "Doctor Who" would bring with it a sense of familiarity. Many of the "Agent Carter" fans who were clamoring for a series renewal would happily watch Atwell on "Doctor Who," provided Chibnall is the first showrunner bold enough to cast a woman in the role.

The introduction of a female Doctor would greatly change the dynamic between the Time Lord and her companion -- and not in a romantic way. Although romance has occasionally entered into the equation, such as with Rose's love for the Tenth Doctor, it's rarely central to "Doctor Who."While the Doctor/companion relationship has always walked the edge of flirtation, it's not really about that.

If Atwell's Doctor were to have a female companion, their adventures could be about exploring the mentor/mentee relationship. Or it could be about a mother/daughter relationship, if the companion was exceptionally young. If the companion were  a man, there could be hints of flirtation, but as in the past, it wouldn't have to be about sexual chemistry or tension. The Doctor doesn't date; he -- or she -- may flirt, but there are worlds to be saved and menacing aliens to be defeated. Who has time for romance?

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The only marital relationship "Doctor Who" has explored in recent years was with River Song. Based on her final episode, "The Husbands of River Song," it's safe to assume her time on the show is done. River was saved to the Library, and that's where she lived out her days. But even if she were still an element of Chibnall's series, who would mind a little flirtation between Atwell and Alex Kingston?

With the news of Capaldi's departure, it's likely Chibnall will begin casting the new Doctor soon. Hopefully he'll think of Atwell's wonderful performances on "Agent Carter" and consider her for the first female Doctor.

Returning April 15 on BBC America, "Doctor Who" currently stars Peter Capaldi and Pearl Mackie.