Deb was on the picket line during the nurse's strike when Jeff dropped by during his lunch. He defused a situation with a man trying to cross the picket line, but then collapsed.
Jeff seemed to recover in the emergency room and was ignored as the ER staff struggled with the lack of nurses. Gregory House became intrigued with his patience and went over to talk to him and his wife. When Deb suggest frustration at the wait, Jeff calmed her down. Deb got upset when House whacked Jeff with his cane to provoke him, but Jeff didn't.
The team started to think Jeff had syphillis, even though he claimed to have been tested for it when he entered the Peace Corps and then had not slept with anyone but Deb since. When he tested positive, he was convinced the earlier test had been wrong. Deb was concerned because she started to believe that Jeff might had cheated on her. She told the doctors that at first, Jeff's constant niceness was annoying, but she later started to find it attractive and fell in love with him.
She got even more concerned when, for the first time since she knew him, he lost his temper with her.
However, Jeff was finally diagnosed with Chagas disease. House explained that Jeff's niceness may have been a side effect of the resulting increased intracranial pressure. House warns Deb that Jeff's behavior may become more like other people's.
Jeff soon recovers, but when his catsup tastes bad and Deb thinks it's fine. He says he probably doesn't like catsup anymore, and Deb starts to look worried.