Captain was a pet parrot owned by the Shopkeeper. They were self-described "servants of the Universe." He considered how he and the Shopkeeper got around to be "privileged information" and was apparently the one who called the shots. Unlike the Doctor, who took subtle approaches to make sure time was undamaged, they took the utmost direct approaches to make sure things stayed in the right order as blind chance couldn't always lead to the correct result. This was the opposite of the Trickster, who caused chaos instead of order.
Biography
The Shopkeeper often talked to Captain while observing Sarah Jane, Clyde, and Rani through his crystal ball during their quest through time. When Sarah Jane and the others returned, it was suggested that Captain was the one who had arranged for them to go on their quest, implying that he was more than an average parrot. (SJA: Lost in Time)
Captain was seen on his perch with the Shopkeeper when he appeared in Sarah Jane's attic to confirm that it was he who left Sky on her doorstep. It was revealed by the Shopkeeper that the Captain was in charge of their duties, making sure things that couldn't be left to chance were taken care of, making them take a more direct approach to correcting history, unlike the Doctor. (SJA: Sky)
