Doubt stars Katherine Heigl as Sadie Ellis, a brilliant attorney at a boutique firm who starts to fall for her charismatic client, Billy Brennan, an altruistic pediatric surgeon recently accused of murdering his girlfriend 24 years ago. Sadie is hiding her growing feelings from everyone, including her close friend and colleague, Albert Cobb, who thinks he knows everything about her. Working on other cases at the practice is Cameron Wirth, a transgender Ivy League graduate who fights passionately for her clients because she's experienced injustice firsthand; Tiffany Simon, a second-year associate who is quickly learning the ropes from Wirth; and Nick, a former felon who earned his degree while serving time. They all consider it a privilege to work for Isaiah Roth, a revered legal lion and "lefty" legend, whose approval is their holy grail. Sadie's decision to become involved with her client could put her career, as well as her happiness, at risk if Billy is found guilty, which means she needs to work even harder to prove reasonable doubt, even if she has some herself.