Brains is a character from the Thunderbirds Are Go! television series. He is a unique and vital member of International Rescue, since he is the man who designed most, if not all, of the organisation's high-tech vehicles and equipment, including the entire Thunderbird fleet. He may well be one of the most intelligent people in the world, and the Tracys are lucky to have him as part of the family, even if he isn't literally a part of the family.