Cassandra Campbell

Cassandra Campbell was a physician's assistant and temporary doctor from Indiana who was murdered by Cathiel Durn Ti Slitheen on April 1, 2004 who became the companion for the Ninth; Tenth and Eleventh Doctors. She first met the Ninth Doctor after treating to his wounds from his second exile to Earth.

She was the only companion to travel with three concurrent incarnations of the Doctor.

Before Death
Cassandra Campbell was born in Indiana on October 23, 1976 to her mother and father who she never spoke of because she had mixed feelings towards how they treat her overall. (TV:The Nightmare Man)

After graduating, she traveled to the UK to become a doctor and/or a teacher to start her life up as she didn't want to continue 'in the magical world of Indiana'. She did send postcards every year however to give her parents hope. (TV: The House With No Upstairs)

Death
Waiting for someone up on a rooftop, Cassandra was on her phone as she waited for the person to arrive, only to find a Slitheen in the same location who needed help in finding the Doctor as it had been implanted with memories of the future where she was with the Doctor. Cassandra put up a fight, managing to scar the Slitheen before it killed her. (TV: The Physician's Apprentice)

Waiting for The Doctor
With a new goal in mind, 'Cass' was promoted to physician's assistant in the spring of 2004. (TV:The Physician's Apprentice) Cass was seen as a not sociable individual between the rest of the staff and whenever asked who she was looking out for, she would always say "a Doctor".

Tired from the trials and tribulations that her Doctor Ethan Armstrong was giving her, 'Cass' killed him as she replaced him as a temporary Doctor.

The next day, a man was brought into her attention, with the name 'Doctor John Smith' as his only identity. Noticing that this man was the Doctor from her memories, she quit her job and took him to her home where she took care of his wounds. However, members of The Dark Horde were able to track the two of them down as she revealed her true identity of Cathiel to him as he was recovering, he was very hesitant to try and send her back to Raxacoricofalapatorius but she was able to explain he mission statement to him and he was able to find that she had no previous convictions in which she was able to become a companion with the Doctor. (TV: The Sainted Healer); (TV: The Physician's Apprentice)

Adventures with The Ninth Doctor
Requesting to the Doctor after a few long nights of working on a new dematerialization circuit, Cass and the Doctor take a day out in which she finds half a machine which sends her as a witness to back in time for the murder of Elizabeth Lewis by Edward Morgan. Alerting herself to the Doctor that she has witnessed this, she goes to find Edward Morgan, who is living alone. Once breaking into the upstairs room, she finds the rest of the machine before Edward decided to go after her. Using the second half of the machine, she was able to see into the future with The Doctor standing over the dead bodies of Cass and Edward. After having a battle outside of the Doctor's house, she convinced Edward to not to kill her, in which he died of a sudden stroke that had entered his body. She lay by his dead body before explaining to the Doctor what had happened. He broke apart the machine to use for the dematerialization circuit. (TV: Ghost Machine)

After having Thanksgiving with the Doctor, Cass went to sleep whilst having a nightmare of something laughing like "the Joker" from DC Comics. The Doctor told her to try and avoid it, but another nightmare occured with a creature starting to appear, it told her that she only had a couple of days left before she would sleep forever as he would take her place in the universe to give everyone else nightmares as his name was The Nightmare Man and he would be able to come into the world if she uttered the name and fell asleep. Cass passed out two days later as she recorded a video for the Doctor to access before speaking The Nightmare Man's name, releasing him into the world. She was sent to a nightmare-hell as the Doctor contacted her by using a couple of sent devices from Sarah Jane Smith in which he was also able to banish the Nightmare Man or what had turned out to be a Vishklar from the Seretti dimension. The Doctor had decided to himself that he had to become Cass's protector because he felt like he wasn't doing enough to protect her. (TV: The Nightmare Man)

The Doctor finally thinking that he can also trust Cass with bigger occupations as he sends her over to Cardiff to get some more extraterrestrial supplies for the rebuilding of the TARDIS. On her way back, she is stopped by a 'man wearing a hood' as he drugs her. She wakes up in her house as she starts acting like she is back home on Raxacoricofallaptorius, the Doctor sends her to sleep to try and find out what has made like this but she wakes up instantly as she sees him as a threat who wants to kill her [a reverse of what happened of their first meeting.], he tries to get as much information out as someone comes to the Doctor, the man who drugged her who was named as The Capper and he wanted to get to the Doctor to take his life but Cass in her anger kills him as the drugs wear off on her because of the connection. They both decide that they both have to be together from that day on wards or else they'll find themselves dead together. (TV: Blunt Madness)

The Doctor and Cass and intruded on December 5, 2004 by U.N.I.T and Capt. Erisa Magambo as they explain that two Zygon races have landed on Earth, one want to take over and the other want to make an alliance that will work with the humans. Because they trust each other, the Doctor allows Cass the chance to come with him to one of the central attack points in Indiana. Cass then finds that her old family home is not too far from the base as she asks for an hours permission before entering her old family home. As she enters her family home, she tests out a method that The Doctor had used with members of The Flesh before where she tested a hot cup of tea and their reaction before they turned out to be Zygons who had replaced her parents. She then killed her parents before returning to the Doctor who had got a call from U.N.I.T's UK offices. Meanwhile, U.N.I.T Officer Oswald (or the leader of the 'taking over' Zygons) had a bazooka weapon on stand by as the plane the Doctor and Cass blew up in the sky, resulting in a victory for the Zygons. (TV: Intervention of the Zygons)

The Doctor parachuted out of the plane, saving his and Cass's life again. However, due to the explosion of the plane - some of the skin off Cass is torn off, which gives her a reason to go and kill again as she separates from the Doctor for an hour or two to use a 'bar skank' to repair her. After this has been finished, Officer Oswald tempts to use the 'real parent's' of Cass to get the Doctor to let her have a weapon to decide what would be done with the Zygons on Earth to either kill them all or transport the two sides off. The Doctor declines as he reaches the London U.N.I.T base before they do, but they have the other weapon... leading the Doctor and Cass into The Black Archives, a further top secret U.N.I.T base in which some of the most hidden artifacts on Earth are. With the Doctor's wit and ingenuity, he was able to deduce both sides of the Zygons into having no actual weapon for them, allowing the side of Oswald's a free chance into space whilst the other side was able to live on Earth. (TV: The Zygon Inversion)

After this happened, the Doctor sensed a storm approaching onwards as he picked something out of his pocket, the TARDIS key which was given to him by Romana before he had to leave for his exile. Cass was able to join him as she witnessed the TARDIS appearing in his home and him able to finally control his ship again, noticing that he was wanting to go right away, she asked if she could pack because she knew this might be her only chance to travel with him, as he accepted before she finally boarded the TARDIS for the next adventure that was to await the two of them. (TV: The Zygon Inversion); (TV: The Entrapped)

Taking her first trip in the TARDIS, she was immediately brought into a floating space-station named Satellite Five with rooms filled with dangers brought by the Doctor's numerous enemies, hers being of an illusion brought on by The Nightmare Man whom she met just recently before. She escapes by thinking up of weapons that she could use against him as the power of dreams still work. She then finds the Doctor observing an observation deck as he is happy to be reunited with her again. He declines to reveal what his horror was, but she finds the lift to access towards FLOOR 500 in which by her illusion of The Nightmare Man, he mentioned that the walls are made of gold and that the big bad wolf had plans for the two. As the two of them arrived on FLOOR 500, they found a couple of programmers still left to run the station, trying to find something that could be hidden as the Doctor helps them breach across to find a battle fleet of Daleks. They set up a meeting, in which the Doctor allows his controlled anger to rage as he vows to wipe "every last STINKING Dalek... out of the sky." as he and Cass make their way back towards the TARDIS. (TV: The Entrapped); (TV: The Oncoming Storm)

With an aim towards reaching the Dalek battle fleet with full force, Cass reminds him that the TARDIS doesn't have shields in that the Daleks may have weapons to blast the TARDIS out of the sky, yet the Doctor has a hidden plan up his arsenal which is that the object they were gathering parts for was actually part of a mini-TARDIS shield that he was going to use for a situation like this. Cass met the Dalek Emperor as both of them found the truth that the Daleks were harvesting humans for the Earth below without them knowing. The Doctor starts to plan a weapon against them, the Delta Wave. Cass doesn't want to join the humans attack as they defend the Satellite, so she does anything to help the Doctor... giving the reason as "I may have been human once, but I want to die with you.". He gives her a plan, to fly the Satellite far enough to a place in which it won't hit the Earth. She gets herself ready... as she is also able to report about the war downstairs, such as finding hidden refuges on FLOOR 0. The Daleks then reach up to FLOOR 500 as she materializes the TARDIS with enough time for both of them to choose to kill the Daleks, in which they do... however, the Doctor is sickened on how he has become "the Great Exterminator", but Cass tells him that he had no other choice because they would have killed him. He then asks her where she would like to go, as she chooses the current Christmas Day that they were gonna witness, as she reveals her affection over him. He slowly guesses that this could be the end, but he is not sure. (TV: The Oncoming Storm)

Travels with The Tenth Doctor
To be added.

Travels with The Eleventh Doctor
To be added.

Memorable Quotes
- Cass, with her first meeting with the Ninth Doctor. - (TV: The Sainted Healer) - Cass's last words to the Ninth Doctor. - (TV: The Only Family in the Universe)
 * "Oh... you're him! I'm here because of you, and now I need to get you and me out of here."
 * "Doctor, you're burning up. I don't think you'll survive... but you have to, because you're the healer of the universe. Please, don't go."