William Landay’s 2012 legal thriller, Defending Jacob, was a bestseller that received a Kirkus Star. Eight years later, it’s getting the prestige-TV treatment on Apple TV+, with an eight-episode miniseries starring Chris Evans, Michelle Dockery, and Jaeden Martell premiering on April 24—although viewers may object to this slight courtroom drama’s excessive length.

The series sticks rather close to the novel, for the most part. A teenage boy, Ben Rifkin, is found stabbed to death in a public park in the wealthy Boston suburb of Newton, Massachusetts, and assistant district attorney Andy Barber gets involved in the case. The investigating police initially investigate a local pedophile for the crime, but they soon find a bloody fingerprint on the victim’s clothes that’s a match for Andy’s son, Jacob. It’s revealed that Ben was bullying Jacob, who is arrested as the cops’ prime suspect. Neither Andy nor Laurie, Jacob’s mother, believe that their child could possibly have done such a thing—even when it’s revealed that Jacob secretly owned a knife. Later, Jacob claims that he found the corpse but didn’t tell anyone, fearing that he’d be blamed.

Andy is taken off the case, but he investigates on his own. He also has his own secret: His father, Billy, is a convicted murderer who’s currently serving time in prison—a fact that Andy has never revealed to his wife and son. As Jacob, his parents, and his attorney prepare for an upcoming murder trial, they grapple with a key question: Could Jacob have his grandfather’s “murder gene”?

Landay unveils a couple of major twists near the end, and they’re good ones that many readers won’t see coming. That said, both the book and miniseries leave a major question unanswered—and the miniseries, in its most notable change, alters the book’s ending in a way that leaves things even more vague. Suffice it to say that this may frustrate some viewers, who will have spent eight hours of their lives waiting for a solid answer.

Overall, the book and series explore standard genre territory; Kirkus’ reviewer even noted that it was “inevitable” that Landay would be compared to Scott Turow. However, it seems as if the author, and miniseries creator Mark Bomback, were also aiming for something deeper—something along the lines of Lionel Shriver’s 2003 novel We Need To Talk About Kevin, whose movie version came out in 2011. Both stories address what makes a kid kill, and what responsibility a parent has for their children’s actions. But Landay’s book, and the resulting miniseries, grapple with these issues in shallow, rudimentary ways. The “murder gene” business is particularly questionable, and mildly ridiculous; it seems to have drifted in from an episode of Law Order: Special Victims Unit—one of the later ones, when its writers simply stopped trying.

This TV production is a very handsome-looking one, and it clearly had money to throw around; the cast is undeniably A-list. They got Captain America himself to play Andy, but despite Evans’ best efforts, his character is never anything more than a bland dad-on-a-mission. Dockery, best known for Downton Abbey, has done fine work in the past, as in the Netflix Western Godless. But as Laurie, she comes off as little more than mildly anxious, even as the mom’s life falls apart around her. (Suffice it so say that she’s no Tilda Swinton, who crushed a similar part in We Need to Talk About Kevin.) Martell, as Jacob, seems game enough, but the story’s structure never allows him to really cut loose. The main problem, in all three cases, is that these are underwritten, unsurprising characters—in the book and onscreen—and there’s only so much that good-but-not-great actors can do to fix it.

The best performers, oddly enough, are relegated to minor roles here. Oscar-winner J.K. Simmons, as Andy’s imprisoned father, makes the most of his few appearances, which recall his brilliant work in the HBO prison-series, Oz; Tony- and Emmy-winner Cherry Jones, as Jacob’s lawyer, Joanna Klein (Jonathan Klein in Landay’s novel) is a riveting presence during her later courtroom speeches; and Get Out’s Betty Gabriel steals her scenes as Andy’s police-detective colleague, Paula Duffy (Paul Duffy in the book), which will make viewers wonder why she isn’t the star of her own prestige cop drama. Even so, all these actors are making the best of so-so material; they’re familiar, stock characters that they make interesting through sheer force of will.

The miniseries will require its audience to summon will of their own—to simply finish it. There’s simply not enough compelling material here to justify eight hour-long episodes, when it could very easily have been a standalone film. As it is, though—it’s a bit of a trial.

David Rapp is the senior Indie editor.