Elton Pope's normal existence is transformed when he comes into contact with the Doctor, starting a period of obsessive fascination in the mysterious man and his blue box. When he was a young child, the tenth incarnation of the Timelord was present on the night his mother died in unexplained circumstances. Elton also caught glimpses of the stranger during the Auton and Slitheen invasion attempts.

He meets Ursula, Mr Skinner, Bliss and Bridget who also try to follow the activities of the Doctor. They form a group called Linda (London Investigation 'N' Detective Agency) and stage regular meetings, forming their own ELO-influenced band in the process.

An eccentric person called Victor Kennedy arrives unannounced at one of the meetings and brings his own information - and agenda - to the table. Soon Victor is in control of the group's activity and decides that they should research and track down the Doctor's companion Rose Tyler as a means to an end.

Elton ingratiaties himself with Rose's mother Jackie, under the prefix of being able to mend some of the appliances in her flat. Elton fends off her amorous advances as he becomes aware of his feelings for Ursula, but then Jackie discovers a picture of Rose in his coat pocket and orders him to stay away.

Upon Elton's return to the group, the numbers have dwindled. It's purported that both Bliss and Bridget have left LINDA, but they are last seen being called back to their Headquarters by Victor. Mr Skinner is then called back to be alone in his presence, but Ursula and Elton unexpectedly return and find their friend has suddenly disappeared from the room.

More importantly, they also see the true form of Victor, as he is revealed to be a monstrous creature who refers to himself as the 'Abzorbaloof'. His victims are absorbed into his body and the heads of Bridget and Skinner can be seen on his skin, still conscious. The same fate befalls Ursula. With the Doctor and Elton next on the menu, some intervention is needed urgently...