Heathcliff and the Catillac Cats (1984)

S1E56 Mungo's Dilemma

Riff Raff spots a newspaper ad featuring a cat resembling Mungo, with a reward attached. The other cats, eager for the prize, betray Mungo by turning him in. However, they soon realize their mistake when they discover he’s been captured by a crazed scientist. Determined to save their friend, they quickly devise a rescue mission and manage to free Mungo just moments before it's too late.