Steph first met Connie at Grace's sports day event at the end of May 2016 and they didn't get off to the best start but put on a friendly facade to each other. On 27 August, Steph's daughter Carmel was admitted to the ED and Connie called social services when it transpired that she'd been abusing her daughter. In anger, Steph chased Connie along a road which resulted in Connie and Grace driving off the road into a ravine. Steph initially drove away from the scene without calling for help but when she later got out of her car to call for help, she was hit by an oncoming vehicle.
On the Monday following the accident, Steph was admitted to the hospital's AAU and was guarded by the police. During the week, another patient became paranoid that Steph was there to hurt Bernie Wolfe which resulted in them having a confrontation; on Thursday Steph attempted to escape but he threatened her with a screwdriver. Fletch intervened but was stabbed himself and rushed upstairs. It can be assumed that Steph was taken back under police guard after her failed escape attempt.
Behind the scenes
Tonicha Lawrence portrayed Steph Sims on Casualty in 2016 for three episodes. She went on to guest appear as the character on Holby City for one episode which aired three days after the 30th anniversary Casualty episode where Steph was hit by a car.