Doctor Who: Every Companion Ranked Worst To Best

The human-with-certain-Time-Lord-traits that has a penchant for calling everyone "sweetie", River Song has a life that is intricately woven with that of the Doctor's. The first time the audience sees her in "Silence Of The Library", the Tenth Doctor (and by extension, us) has no idea who River Song is, despite the fact that she claims to have a deep and long history with him. As the series goes on, and River shares adventures with the Eleventh and Twelfth Doctors, it becomes apparent that their encounters occur in reverse order: the more times the Doctor meets River, the less she actually knows about him.

This didn't stop the Doctor from accompanying River on many more adventures in his eleventh incarnation, leading to the two eventually marrying in order to stop the destruction of the universe as a result of all time happening at once (just watch the episode). As a result, not only Amy and Rory now the Doctor's parents-in-law, but River and the Doctor, finally start to understand why they are so intrinsically linked to one another, even though the Doctor will become less and less aware of River every time they meet. With such a bewildering timeline, spoilers concerning each other's lives were bound to come out, which they inevitably did.

River Song was practically a mirror image of the Doctor. Smart, brazen and mysterious, she was pretty much a female Doctor before the Doctor became the female Doctor, and every episode she was in proved to be first-class and memorable. No matter which other companions joined her, or which incarnation of the Doctor she was interacting with, the chemistry that River shared with them was never anything less than excellent.

Having featured alongside the Tenth, Eleventh and Twelfth Doctors (not including the highly recommended Big Finish audio dramas in which she interacts with other older incarnations), it's high time that River Song was introduced to the Thirteenth Doctor. The fandom demands it.