9. Tegan Jovanka
Tegan was one of the longest serving companions on Doctor Who, and so has a special place in the programme for that reason alone. Sure, she could be a touch obnoxious at times but she was always fierce, often brave and an integral part of the show. Her departure, after three years in the role, was bound to be emotional. And oh, it really was. In Resurrection of the Daleks, a story boasting a higher body count than even Steven Moffat could dream of, the slaughter of so many people proved too much for her and she departed. Running off into the world, absolutely heartbroken at what she's seen. "It can't end like this!" The Doctor cries after her, but not even he can stop the inevitable. Initially, I admit, I thought Tegan's departure came out of nowhere. But on reflection it actually made perfect sense. Travelling in the TARDIS is wonderful, but is also presented as being deeply traumatizing. In her time with the Doctor Tegan witnessed the murder of her aunt and the death of the brat also known as Adric, was possessed multiple times by one of the more terrifying villains that Doctor Who has to offer and was forced to go up against both Daleks and Cybermen. That's an awful lot of trauma for any mind. It seems natural, then, for her to finally break under all the stress. And her departure, when properly thought about, feels almost entirely natural as a result. It's not dignified and calm, it's brutal and feels an awful lot like a punch in the stomach. Tegan departs in tears, and leaves the Doctor and Turlough devastated behind her. It isn't elegant, it isn't particularly nice but it feels truthful and shows just how hard it can be to leave the whole universe behind. I mean, it's hard enough even watching the show and knowing that everything is fictional. Another part of what makes Tegan's departure so good is that it opens the door for other departures. The very next story is Planet of Fire, where Turlough sadly leaves the TARDIS. And both of them build to the sheer glory of Caves of Androzani, when the Fifth Doctor leaves and the Sixth Doctor booms loudly into his place. It's a trilogy of tears, and Tegan's departure plays a big part in that. The strength of her departure carries the series on to one of the best things ever shown on television. Tegan could be obnoxious at times, but she could also be incredibly endearing. She was an integral part of Peter Davison's era, and the show wouldn't have been the same without her. At first her departure seemed out of nowhere, but on further thought it was perfectly understandable and wonderfully natural. She showed the dark side of adventuring with the Doctor, as well as the light and for that her departure is one of my favourites.