Victoria met the Keeper when she visited Traken with the Second Doctor and Jamie McCrimmon. She was in the Grove looking for flowers when he appeared. She was unnerved by him knowing who she was, so she fled.
She saw him again when he appeared in her rooms. He offered her a flower and asked her to stay with him. Once again, Victoria fled.
She later learned that the Keeper, along with the other Trakenites, were acting strangely because alien astronomer Neverglade's model universe was disturbing Traken's delicate biomatrix. Victoria apologised to the Keeper.
Unknown to Victoria, the Keeper left a piece of his mind in Victoria, which allowed the creation of Viola, a part of Victoria that could continue travelling the universe after she left the Doctor. (PROSE: The Astronomer's Apprentice)