Get Smart (1965) : 5x11

Max is bewildered when his young contact dies of old age. Max goes to meet CONTROL Agent Carruthers and finds Carruthers dying of old age. The problem is that Carruthers is only 28 years old. After that, more and more agents are rapidly aging and dying, thanks to a new invention by KAOS, Dorian Gray Paint. The paint ages the real person once it's put on a picture of that person. They turn Max, 99, and the Chief into senior citizens right before they locate KAOS HQ.