If you'll remember, Dr. Collins was a cool-headed, uber-knowledgeable anchor in the storm of PTMC's chaos. Ifeachor delivered a brilliant end-to-end performance, especially when Dr. Collins tragically suffers a miscarriage in the middle of her shift. All of this is exactly why fans of The Pitt were shocked to learn that Ifeachor would not return for The Pitt season 2. In season 2, episode 4, The Pitt finally gives us that in-universe explanation for why Dr. Collins is no longer working at PTMC. "Dr. Collins finished her residency, took up a job in Portland as an attending physician," Whitaker says.