She was portrayed by Lauren German. Leslie originally came from Firehouse She was a lesbian, something Peter Mills discovered when the other firefighters tricked him into making a pass at her.
She was previously in a three-year relationship with a woman named Clarice Carthage , who eventually left her, and ended up marrying and having a child with a wealthy man named Daniel Schwartz. This seems to have instigated the commitment issues she had. Leslie was killed in the line of duty on May 13, after injuries she sustained in a partial building collapse.
In " A Nuisance Call " , she and Dawson are called out to Darryl, a regular caller's, house to help him with his insulin injection, something he could easily do himself. They're both annoyed at him, and he is obviously infatuated with Shay. He pulls out a gun in the middle of the call, and Dawson tries to get him to put it down by yelling at him, but Leslie takes a different approach, telling him that she's in love with him too, and they can go to elope in Las Vegas if he puts down the gun.
Both of their approaches fail and he shoots himself in the head in front of them, blood splattering over both of them.
This affects Shay and Dawson differently, with Shay becoming despondent and withdrawn, causing an argument where Dawson pulls rank and they both declare their friendship over. She is later seen drunk with Otis , saying it was great that he moved in, and laughs with him until she starts sobbing. Otis agrees to keep her breakdown secret from Severide, and she walks away. In reference to the episode: " Real Never Waits ".
