For years, Bob Harper and Jillian Michaels appeared to have great chemistry onscreen while filming "The Biggest Loser" together. But a new docuseries about the NBC weight-loss competition has fans wondering if the dynamic duo actually got along in real life.

Bob Harper didn’t hear from Jillian Michaels after his heart attack in 2017. In a new interview with The Guardian, Harper, 59, said many people from “The Biggest Loser” reached out to him after the near-fatal health incident — but not Michaels, 51.

"Biggest Loser" trainer Bob Harper opened up about his 2017 heart attack, including the reaction of his costar Jillian Michaels.