Mariska Hargitay’s character on “ER” is more likely to burst into tears than bust bad guys. Before she debuted as Detective Benson, she played the sweet and sensitive Cynthia Hooper in 13 episodes of the medical show’s 4th season. She appears for the first time in the 1997 episode “Something New” as an applicant for the desk clerk position at Chicago’s County General Hospital (via IMDb). After an awkward interview with Dr. Mark Greene (Anthony Edwards) and nurse Carol Hathaway (Julianna Margulies), Greene hires Cynthia, even though she isn’t entirely qualified.
After sharing a kiss in the episode titled “Ground Zero,” Mark and Cynthia enter a brief but passionate romance. Their relationship continues throughout Season 4 until the 14th episode “Family Practice.” Dr. Greene travels to San Diego to care for his hospitalized mother. Unbeknownst to him, Cynthia has followed him there. During an uncomfortable conversation on a pier, Mark reveals he does not know if he loves Cynthia. The couple split up before she catches a flight home.
Hargitay made her last appearance as Cynthia Hooper in Season 4 Episode 16 titled “My Brother’s Keeper.” When Greene returns to Chicago, he finds out that his now ex-girlfriend has moved and quit her job at the hospital. He tries to win her back at her new apartment, but Cynthia turns him down. They break up for good.