Joe, Eddie, and Barry work at the police station in pilot episode.
Barry is treated at the hospital after the accelerator explosion in pilot episode.
Cisco, Barry, and H.R. head to the university to talk to Tracy Brand about her research in episode 3x20 "I Know Who You Are".
Diggle, Lyla, Deadshot, and Cupid run a hostage rescue mission at a hospital in episode 3x17 "Suicidal Tendencies".
Oliver attacks a group of Ghosts on the roof of the psychiatric hospital and is assisted by Ray in his A.T.O.M. suit in episode 4x07 "Brotherhood".
Julia stays at a rehab facility where she meets a different kind of magician in episode 1x08 "The Strangled Heart".
Kady, Penny, and Quentin head to the hospital where Dana had her child to look back in time and discover who adopted the baby in episode 2x08 "Word as Bond".
In a flashback, Monica Reyes is recruited by the Cigarette Smoking Man while he is recovering from his burns in episode 10x06 "My Struggle II".
Scully is taken to the hospital for treatment after her seizure in episode 11x01 "My Struggle III".
Shawn and Gus head outside and Nick Conforth gets their attention to give them intel about the case.
Rebecca analyzes a photograph she found at a crime scene in pilot episode.
Emerson visits Lucy in the hospital after she is shot in episode 1x03 "Kit Nelson".
Rebecca and Emerson search the lab where Johnny McKee was mixing his poisons in episode 1x07 "Johnny McKee".