Brain is the tritagonist in the Inspector Gadget franchise. He is Penny's 4-(later 5)-year-old dog who is the only one that knows Penny is the one who solves Gadget's missions.
This page may refer to:
- Brain (DiC) - Brain as seen in Inspector Gadget (1983 TV Series)
- Brain (Disney) - Brain as seen in the Inspector Gadget (film series)
- Brain (2015 series) - Brain as seen in Inspector Gadget (2015 TV Series)