Mad Dog is a character that appeared in an episode of the animated sitcom King of the Hill.
Mad Dog is a member of the Arlen Gun Club who was formerly in prison for killing a man and has disdain for Gun Club President Dale Gribble. During the campaign for Gun Club President, Dale accidentally discharges his gun while telling a story, losing the respect of the other members. Using this to his advantage, Mad Dog runs a successful campaign and wins the President position himself, even inviting the other members to a inauguration party at his cabin.
Meanwhile Dale has lost confidence, making Hank Hill sending him on a phony mission as "Mr. Big". After the mission, Dale feels threatened by Mr Big, thinking it's Mad Dog and declares he's going to kill him, but instead plans to flee to Costa Rica. Meanwhile, thinking Dale was going after him, Hank, Bill and Boomhauer head to Mad Dog's cabin to look for him, but get themselves trapped and captured by Mad Dog, who ties them up and tortures them into confessing who sent them. While he's away, Hank calls Dale and lets him know of the situation, with Dale attempting to come to the rescue, but instead gets himself caught by Mad Dog, but unbeknownst to him, Dale has called some Flower Shop people to come over, with everyone thinking they're CIA agents (based on one of the stories Dale has told). A frightened Mad Dog tries to urge everyone to help him fight off the "CIA agents" but when they refuse, he jumps out the window and escapes for fear of being captured, but not before blowing up the cabin with a remote-controlled bomb. Thankfully, no one was inside during the explosion.