Allison was born in the Herefordshire village of Lower Burford to a farming couple. Her birth was very difficult for her mother, resulting in her being unable to have further children. Allison had a poor relationship with her father. She believed that her father always resented the fact that she was not a boy and that he always cared more about his animals than his family.
Allison was not fond of Lower Burford, describing it as "a hillbilly hellhole" in 1965. She left home to attend the University of Cambridge in 1956, at a young age, and did not return until her father was taken ill nine years later. She had deliberately left young in order to force her father to ask why she'd left, but he never did. (AUDIO: The Forgotten Village) At Cambridge, she was the top of her class and noted as someone to watch by the government. (AUDIO: Changing of the Guard)
In November 1963, she appeared on site with Professor Jensen and witnessed a Dalek kill several soldiers attached to the ICMG under the command of Group Captain Ian Gilmore. It was at 76 Totter's Lane that she met the Seventh Doctor and Ace, whom she later assisted in defeating both the Renegade and Imperial Dalek factions who were searching for the Hand of Omega. (TV: Remembrance of the Daleks)
She was sent by Toby Kinsella to infiltrate an anti-nuclear commune after the assassination of Stephen Mulryne. She met with Martin Regan for membership. She was hypnotised by Martin to kill 'John Rutherford', Gilmore and the herself. Fortunately, because she was told to kill John Rutherford, her controlled mind was unable to complete her instructions as she recognised 'Rutherford' as the Doctor, allowing him to break her programming. She then proved vital in helping the Doctor and Gilmore identify another key player in the conspiracy. (AUDIO: 1963: The Assassination Games)
She and Julian had started dating in 1961 but, after three years, she was becoming concerned as to what he wanted from their relationship. When the artificially intelligent Sentient Engine Generator 2 computer, also known as Sen-Gen, had tapped into her mind and amplified her subconscious fears, she went to Julian's flat and cut all of his clothes with the exception of his tennis outfit into shreds and wrote, "Why don't you love me enough?" in Pastel Pink lipstick across his wardrobe.
Under Sen-Gen's influence, she later threatened to shoot Julian. However, he told her that she could resist Sen-Gen as she was the strongest willed person that he knew. He explained that he did not take their relationship any further as he did not want to hold her back. In order to reaffirm his love for her, he proposed to her. She accepted and put the gun down. Julian later reflected that they would have to come up with a story to tell not only Allison's mother, whose presence he claimed was enough to trigger a psychotic episode, but their children in years to come. (AUDIO: Artificial Intelligence)
To Alison's dismay, Julian turned out to be part of a military coup against PM Harold Wilson and he hadn't really loved her: it had all been part of the coup plot, with him able to resist Sen-Gen as he knew he was lying. To save the Prime Minister, she had to shoot him dead. (AUDIO: State of Emergency) For months after, she surpressed any problems and threw herself into her work. Rachel Jensen noted that she had been acting different since then but Alison waved it off. (AUDIO: Manhunt)
In 1965, Rachel joked that Allison drank so much tea that she kept the East India Company in business. (AUDIO: Unto the Breach) She was brainwashed by Templeton to think that he was Toby and another Captain was Gilmore. (AUDIO: New Horizons)