With Doctor Who's 60th anniversary on the way, fans are bittersweet as they reflect on the end of Jodie Whittaker's Doctor Who era. While experiencing an emotional low from Thirteen's exit, fans are also excited to see David Tennant and Catherine Tate return as the 14th Doctor and Donna Noble respectively for the show's 60th anniversary.

With Billie Piper having returned as The Moment in the show's 50th anniversary special, one notable companion from the Russel T Davies era has been absent in the anniversary specials: Freema Agyeman's Martha Jones. Agyemen first joined the show as Adeola in Season 2, Episode 12, "Army of Ghosts." Producers were so impressed with her performance that she was eventually cast as a full time companion in Doctor Who Season 3 in 2007. She encountered the Doctor at a hospital while attending medical school, and started to adventure with the Doctor from there.

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Doctor Who's Martha Was an Incredibly Loyal Companion

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One of Martha's best traits was her fierce loyalty to the Doctor. She earned her TARDIS key in Season 3, Episode 7, "42," when the Doctor was infected with an unknown virus from the sun. In one of her bravest moments, she hid the Doctor's identity as a Time Lord by pretending he was the human John Smith in Season 3, Episode 8, "Human Nature" and Episode 9, "The Family of Blood." In the latter two episodes, Martha encountered racism and other abuse while hiding Mr. Smith from the shape-shifting "family." She also stood by his side and supported him when the terrifying Weeping Angels sent the two back in time, leaving them stranded without the TARDIS. Through thick and thin, Martha Jones has been there for the Doctor, in some of the most dire situations.

Martha Had a Complicated Relationship With the Doctor

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Martha quickly developed a crush on the 10th Doctor when the two started to adventure together. Their relationship was complex as the 10th Doctor was still grieving Rose, leaving Martha to suffer in Rose's shadow. Not only did Martha have feelings that were not reciprocated, but her adventures with the Doctor led to the Doctor's arch nemesis, the Master, imprisoning and torturing her family. While it wasn't directly the Doctor's fault, Martha's family would have been fine if it weren't for her interactions with him. These layers add nuance to Martha's character, which make for quite interesting conversations between her and the famous Time Lord.

Martha Summoned the Doctor To Earth

Martha Jones stands in front of Donna Noble and the Tenth Doctor in Doctor Who

After she chose to leave the TARDIS after the Master took over Earth for a year, Martha still made an active effort to be a part of the Doctor's life, even joining him and Donna in Season 4. She called him with a phone she left in the TARDIS in Season 4, Episode 4, "The Sontaran Stratagem," and helped her defeat the Sontarans in Season 4, Episode 5, "The Poison Sky." She accepted a position in UNIT and referred the Doctor to her superior officer, whom he didn't approve of at first. However, after speaking with the Doctor about working from the inside, he accepted her position, understanding that staying behind on Earth was the best decision for her and her family.

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Doctor Who promotional material features David Tennant and Martha Jones.

Being one of the longest running sci-fi programs in television history, fans have a lot to thank Doctor Who for. Every week, The Doctor and their companions travel to new and distant places, whether in Earth's past or the future on an alien planet. While some experiences are exciting, there are some which can be quite traumatic, and this is showcased firsthand with Martha Jones's development as a character.

Martha had no idea what she was getting into while traveling with the Doctor. She fell for him, knew he didn't feel the same way and stood by him anyway. Through life and death situations, Martha Jones has been there for The Doctor, even maintaining her relationship with him from planet Earth. All of these reasons and more is why Doctor Who's 60th anniversary is missing an important piece to the Whoniverse puzzle.