The following contains spoilers from the first two episodes of For lack of evidencenow streaming on Apple TV+.

After just two episodes For lack of evidence has several changes compared to Scott Turow’s legal thriller from 1987.

Like the novel and the 1990 film starring Harrison Ford, the story revolves around the shocking death of Carolyn Polhemus, a prosecutor in the Chicago District Attorney’s Office—though here the crime scene suggests not a botched sexual restraint but a heinous murder reminiscent of a previous case Rusty and Carolyn worked on. And while evidence in the novel included Rusty’s semen in the victim’s body and a bar glass with his fingerprints on it, the initial search for clues in the TV series does not lead him to the crime scene.

The TV series doesHowever, they reveal that Carolyn was pregnant at the time of her death – with Rusty’s child.

But perhaps the biggest deviation so far from the For lack of evidence In the novel and film, the character Rusty (played by Jake Gyllenhaal) is chosen to be his defense attorney against the murder charge.

There is no defense attorney figure here, Sandy Stern (played in the film by the late Raul Julia); instead, Rusty asks his longtime friend and mentor, Raymond Horgan (Bill Camp), to stand up for him. The thing is, Raymond was just fired as district attorney because Rusty (noticeably?) made no progress in the investigation into Carolyn’s death; Raymond also feels extremely betrayed by Rusty, who concealed his affair with a colleague, particularly in the course of her murder.

Why did showrunner David E. Kelley, whose previous book adaptations Big little liesmake this big change in Rusty’s defense?

“I love the character Sandy Stern,” Kelley tells TVLine, “but the sense of betrayal that is so prominent in the show is something I wanted to explore with Raymond as well.

“We think of infidelity as something between a man and a woman, but the tentacles reach much further – they penetrate friendships,” Kelley notes. “Rusty, (wife) Barbara (played by Ruth Negga), Raymond and (his wife) Lorraine (Elizabeth Marvel), they were a foursome. They are friends, and that relationship was destroyed by infidelity.” (As in the book and on the screen, Barbara knew about Rusty’s affair long before Carolyn’s death.) “Raymond’s political career may have been crippled by this affair and Rusty’s inability to be honest with him,” Kelley adds. “Maintaining that sense of betrayal in the relationship between Rusty and Raymond and infusing the trial with it was what interested me. It wasn’t about escaping Sandy Stern, it was about getting to Rusty/Raymond.”

Having Raymond at Rusty’s side will also add some juicy drama, as the former district attorney will have to compete against “Thing 1 and Thing 2,” the ambitious duo that replaced him: Nico Della Guardia (OT Fagbenle) and Deputy Attorney General Tommy Molto (Peter Sarsgaard).

“The old and the new DA are in direct conflict with each other. It’s like the old lion against the young lion!” said Fagbenle in the preview.

As the charges against Rusty build and eventually go to trial, “there is a lot at stake both professionally and personally,” says Fagbenle. “The way things play out with these dynamics will very intensive.”

Would you like to know more? For lack of evidenceor for another TV show? Email [email protected] and your question might be answered on Matt’s Inside Line!