Killing bugs is killing Dale!
Dale is forced to reevaluate his extermination business when his lungs begin to fail from the toxins he sprays; plus, smoking doesn't help. His lack of bug killing sends Dale into a midlife crazed frenzy. He begins helping Joseph with a cockroach project, and his wife, Nancy, stops sleeping with him because he's out of work.
After extensive pressure from Nancy and Hank, Dale decides to take a job with a local company that makes adhesives. His new job doesn't allow him to smoke or wear his hat and sunglasses, but it does reignite his marital flame. It doesn't take long for Dale to get promoted, though, when his boss (Lisa Kudrow) realizes Dale's unique gift for exterminating (i.e. firing) employees.
Hank and Nancy begin losing respect for Dale because of his vicious firing practices. But instead of changing, he starts getting worse, that is, until a roach problem surfaces at work. Dale figures out he can exterminate roaches by hand, without noxious fumes, and get back to the life he love.