Sometimes it's like people forget that in the world of Doctor Who, Shakespeare wrote his most famous sonnet for Martha Jones. Martha (Freema Agyeman) was cool enough to inspire the Bard — and cooler still for turning him down — but she's always left out of conversations about the Doctor's best companions. On one level, that speaks to how crowded the field is: The point the show wants to make, as the Doctor loses irreplaceable friends but still finds room in the TARDIS for new ones, is that people are too unique to be compared to each other. But when it came to Martha, the Doctor couldn't stop trying.

The first Black companion in the history of Doctor Who, Martha joined the sci-fi revival in 2007, following the exit of Billie Piper's massively beloved Rose. Rose occupied a unique spot in the world of Doctor Who, where the golden rule has always been "no hanky-panky in the TARDIS": She was in love with the Doctor, explicitly, and he loved her back, even if the long and sexless history of the franchise prevented him from telling her before tragedy struck.

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How can anyone compete with star-crossed romance? The sparkling chemistry between Rose and the Tenth Doctor (David Tennant) cast a long shadow over Martha when she made her debut at the start of Season 3. Her uphill battle to make the Doctor — and the fans — view her on her own terms was complicated by the fact that she developed her own unrequited crush on the Time Lord, which only made Rose loom larger in her story. Both the best and the worst aspects of Martha's arc are tangled up in her infatuation with the Doctor: The idea that every woman in the Doctor's path was hopelessly in love with him was insulting (then-showrunner Russell T. Davies finally put that idea to rest with the next companion, Catherine Tate's Donna, who was never anything more or less than the Doctor's best friend), but, to be fair, Davies wrote almost everyone in the Tenth Doctor's orbit like they had a crush on him, from Jack Harkness (John Barrowman) to, literally, William Shakespeare. And Martha's strongest moments came when she stood knee-deep in her own feelings and demanded dignity anyway.

At its best, Martha's story was about a woman grappling with her self-respect in the midst of an unbalanced, often unhealthy relationship. Female characters in her shoes are often painted as pushovers, but Martha pushed back. Outside her dynamic with the Doctor, she had nearly everything in her life handled: She was a medical student. She kept the peace in a lively but strained family. In crises, she was cool but never detached. Martha was bold, clever, curious, and empathetic, and none of that changed because she loved a man who didn't feel the same. She felt what she felt, and then she walked the planet for a year in order to save humanity from a fascist dictator. Martha Jones had things to do.

Freema Agyeman, Doctor Who Photo: BBC

As a Black woman traveling through time, Martha often had to do more work to stay alive than her white counterparts would have — a reality the Doctor never fully grasped. "I'm not even human," he shrugged when he took her back to the Elizabethan era. "Just walk about like you own the place. Works for me." The Doctor couldn't be bothered to see the world from her perspective. Twice, Martha had to get jobs to support him during their trips to the past, including one particularly demeaning stint as a boarding school maid in pre-World War I England, where boys mocked the color of her skin and a white female nurse dismissed her education. Martha spoke up against the worst treatment, but she still stayed put out of loyalty to the Doctor. And when the temporarily amnesiac Time Lord took a shine to that nurse, Martha was prepared to welcome her into the TARDIS. In that sense, she and the Tenth Doctor really were perfect for each other: They were both self-sacrificing to a fault.

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But Martha also shared the Doctor's tendency to bury emotions, which made it even more satisfying to see her stand up for herself. Despite the fact that she wasn't exactly getting validated around every corner, Martha refused to let the Doctor treat her like a rebound, and when she realized she was putting her life on hold waiting for him to love her, she backed out. "I spent a lot of time with you thinking I was second best," she told him, "but you know what? I am good." No companion in the modern series got a healthier exit from the TARDIS than Martha Jones did: She knew when it was time to leave, and she walked away whole.

Martha went on to appear on spin-off series Torchwood, where she was surrounded by people who valued her intelligence and expertise. She then returned to Doctor Who as a full-fledged doctor herself, sporting a ring from her equally gorgeous medical doctor fiancé. (In the end, she inexplicably married Rose's ex-boyfriend Mickey instead, an about-face that felt like it was more about giving Mickey closure than it was about Martha.) After a season spent wrestling with jealousy, Martha found community; she befriended Donna and celebrated when the Doctor reunited with Rose. The mutual respect she found with his friends was a well-deserved grace note at the end of her story. But it may have been too little, too late.

David Tennant and Freema Agyeman, Doctor Who Photo: BBC

No matter what she accomplished on her own, Martha's epitaph was already set in stone: She was the one who pined for the Doctor. The pair's difficult dynamic, though it made for plenty of memorable episodes, was harder to embrace than a buddy comedy or a romance that burned up a sun. That was the point. Her story challenged the narrow definition of love a female character could be satisfied with. Martha took a tired stereotype — she has her life together but can't hold down a relationship — and made it about a woman's self-respect.

Still, Doctor Who didn't do Martha justice when it came to the impact she had on the Doctor. Recognizing how he'd mistreated her only fueled the Doctor's guilt, not his urge to change. Her time in the TARDIS toughened Martha and turned her into a fighter, but rather than examine how she felt about that, the show took the Doctor's perspective, focusing on his fear that his personal Midas curse was to turn people into soldiers. Martha was too often an afterthought in her own story. She reminded audiences that the Doctor was fallible, but her season ended by painting him as the world's savior — a legend Martha herself stoked by traveling the world to tell his story — so his pedestal was too easily rebuilt.

When she first met the Doctor, Martha told him, "As far as I'm concerned, you've got to earn that title." It took the series over a decade to understand that doctors have to listen. Doctor Who fumbled Martha's legacy in the short term, but she laid the groundwork for change down the line, easing the show toward a future where a female Doctor (Jodie Whittaker) could travel back in time with a Muslim Pakistani woman (Mandip Gill) and a Black man (Tosin Cole) who acknowledged the racism and sexism at work in their lives but weren't defined by it. Martha walked the Earth so they could run. Martha did what she always did: She put in the work.

Freema Agyeman, Doctor Who Photo: BBC

This week, TV Guide is celebrating some of TV's most underrated female characters. As part of Women's History Month, we're paying tribute to Justified's Winona Hawkins, looking at how Sex and the City's Miranda Hobbes became the face of a movement, and more. You can check out all our Women's History Month content here.

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