Controversial from the beginning, River Song made a huge impact on Doctor Who when she first appeared in Series 4's two-part story, "Silence in the Library" and "Forest of the Dead." From the beginning, her character was a mystery, appearing to know The Doctor despite him not having met her previously. As her story developed, even more surprises about her character came out.

An assassin, a thief, an archeologist, and a human with Time Lord DNA, the mystery of River Song spread across seasons and different incarnations of The Doctor. Her story was cyclical, with her beginning also being the end of her story, and the show eventually caught up with her timeline. With her character being dead in the show, will River Song ever make a return to the TARDIS?

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River Song on Doctor Who

River Song, played by Alex Kingston, and also known as Melody Pond and the Doctor's Wife, first appeared in Series 4 of the Doctor Who revival. Episode 8 of the series began the two-part story "Silence in the Library" / "Forest of the Dead," in which the Tenth Doctor and Donna Noble land on a 51st-century library planet that has been long abandoned. There, they team up with a group of archeologists to discover just what happened to cause the abandonment of the building. That group of archeologists is headed by Professor River Song.

In the episode, the shadows in the library have become home to the Vashta Nerada, flesh-eating creatures that use shadows to hunt their prey. When River and her team arrive at the library, it's clear that she knows The Doctor, even though he doesn't seem to know her. Due to the pair's time travel-based relationship, from the Doctor's perspective, they have never met, while for River, they are well known to each other. Along with this, she also knows the Doctor's true name.

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By the end of the storyline, River is dead, with her consciousness saved in the library's computer database along with other library patrons that the system saved after it was besieged by the Vashta Nerada. This episode is both River's end and beginning, with her further appearances taking place at earlier points in her timeline. Following this story, she doesn't appear again until Series 5, with a whole new Doctor and companion to baffle with her knowledge of the future. With her, she carries a diary, filled with spoilers for the Doctor's future and knowledge of an old adversary, the Weeping Angels.

The next time River appears is in the Series 5 two-part finale, "The Pandorica Opens" and "The Big Bang." The storyline revolved around a box known as the Pandorica that contained the most destructive force in the universe and the countdown to its opening. Throughout her appearances up to this point, it's clear that something about River engenders trust from the Doctor. Her knowing the Doctor's true name notwithstanding, River is still a criminal gallivanting through space and time, stealing things and befuddling people with her hallucinogenic lipstick.

River Song's main arc took place during Series 6 where she appeared in six episodes, starting out with "The Impossible Astronaut" and The Doctor's death. Series 6 is where audiences finally learned the origin of the mysterious River Song: she is actually the grown-up child of Amy and Rory Pond. River Song is actually Melody Pond, conceived by the Ponds in the TARDIS imbuing her with Time Lord DNA and some minor regenerative abilities. River is the third incarnation of Melody, who was stolen from her parents by The Silence and conditioned into becoming an assassin. Her main mission is to kill the Doctor. It's revealed that Melody gave up her remaining regenerations to revive the Doctor after poisoning him beyond his ability to regenerate. Thus, it's fairly certain that audiences won't see a new regeneration of River — if she does reappear, it will be in one of the incarnations we have already seen.

Possible Stories For River's Future

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River's long and winding storyline seemingly ended with The Twelfth Doctor upon the planet Darillium, where they spent a 24-year-long night together before she made her way to the library where audiences first encountered her. But, is this really the end of River Song? Arguably, it doesn't have to be. River Song's entire arc on the show was out of order and out of time. There's no reason she can't make future appearances alongside different incarnations of the Doctor at different points in her timeline.

Much is untold about River's character and adventures. While parts of her youth and conditioning by The Silence are known, she led a fascinating life by all accounts. Diving more into her past and her time spent away from the Doctor could bring the character back into the show. Random encounters with River Song are very much a part of her characterization, and it's only natural that she would return in the same way. Exploring her character more, especially in wake of the Timeless Child revelations and how it has affected the regenerative history of the Doctor, could make for some interesting stories. The Doctor has had previous regenerations, without memory of them now. This means there is plenty of scope for the two to have crossed paths at different points without even knowing it. Perhaps River will reappear in such a scenario, where only the viewers know the truth.

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