Doctor Who: What Happened To Every Companion?

Next was the third era - and the most drastic staff and formula shifts in the entire franchise until Moffat becomes show runner. Having been forced to regenerate and stranded in the late 60's, The Doctor has to work with UNIT in order to fight against alien threats. While he had been introduced last season, this is when the one and only Brigadier Alistair Gordon Lethbridge-Stewart really comes into his own as The Doctor's most trusted confidant. However, we will not discuss him in further detail until his last appearance.

The Doctor's real companions this season include Liza Shaw, Mike Yates, and Jo Grant. Liz Shaw ws the first companion of The Doctor, the official scientific adviser of UNIT, and the first one to leave. After an adventure involving the Silurians, she takes a job from UNIT to become the official liason between Earth and the Silurians, while also swearing to find a cure for a disease that had been ravaging them. Her farewell to The Doctor was short, with her explaining while he played with a caterpillar, because if she had to say it to his face, she'd be overcome with emotion.

Next up is Mike, who has easily one of the most fascinating journeys of any companion. Starting off as the Riza Hawkeye to the Brigadier Stewart's Mustang, he was a tough, no nonsense UNIT officer through and through. But after a sentient computer named BOSS brainwashes Mike into turning a gun on The Doctor, his friend, Mike was left emotionally devastated. He went on leave and eventually resigned, only coming back occasionally to assist future Doctors.

And finally, we have Jo Grant. A civilian employee of UNIT, she traveled with The Doctor after The Time Lords lifted their exile on him. Her leaving was The Doctor's decision, when he found out that she was engaged to be married. Saddened by knowing he has to let a friend go, but wanting her to be happy, The Doctor gulped down an entire glass of champagne and walked out when her back was turned. Thankfully we would see Jo one more time in The Sarah Jane Adventures, when she teams up with the eponymous former companion to help the 11th Doctor fight some aliens.