Leslie gained further prominence for portraying Donna Troy / Wonder Girl on the DC Universe / HBO Max superhero series Titans (2018–2021) and was part of the main cast during the second and third seasons.

[4] In 2012, Leslie portrayed Angie in the psychological thriller film Chained, a young woman abducted by a serial killer to be murdered by his reluctant apprentice.

[8] DVD Talk reviewer Jamie S. Rich praised her performance and although critical of the overall film, wrote that Leslie played her character "with heartbreaking gravity".

[9] After being cast in the unaired pilot for Widow Detective, Leslie appeared on the series Rizzoli & Isles as Ms. Barlow, the law clerk of a murdered judge, and Revenge as Bianca, a maid working for the Grayson family, in 2013.

[13] She also appeared as sociopath Kelly Donovan on an episode of Hawaii Five-0 and Des, a former girlfriend of Penn Badgley's character, in the film Parts per Billion during the year.

[20] In 2017, Leslie played Sarah Ellis, the aide to Helen Hunt's fictional North Carolina governor, as a regular role on Fox's miniseries Shots Fired.

[21] Additionally, she portrayed sexual assault victim Holly Greco on an episode of Gone and Amber, a young woman unaware of her boyfriend's homosexuality in the short film Down, directed by her brother Dylan.

[24] Later in the year, Leslie became the first actress to portray Donna Troy, the original Wonder Girl, in live-action with her casting on the DC Universe series Titans.

[29][30] Between the second and third season of Titans, Leslie appeared in the 2020 music video for the Rhye song "Helpless" as a yoga instructor who becomes the subject of a student's romantic fantasies.