If you read the Remarkably Bright Creatures book, then you know that the Netflix movie, which began streaming on Friday, makes a few changes to the best-selling 2022 mystery novel written by Shelby Van Pelt.

Directed by Olivia Newman (Where the Crawdads Sing), who also adapted the script with co-writer John Whittington, Remarkably Bright Creatures tells the story of a lonely, 70-year-old widow named Tova (Sally Field) who is still grappling with the death of her son, decades later. She doesn’t go to therapy, but she does share her thoughts with the giant octopus, Marcellus, at the aquarium where she works as a cleaning lady. Marcellus can’t speak back, but the audience gets to hear his thoughts thanks to a delightful voice over narration from Alfred Molina.

Author Shelby Van Pelt served as an executive producer on the film, and read every draft of the script, director Olivia Newman told Decider in a recent interview.

“[The notes] were often very minimal,” Newman said. “Little details like—you wouldn’t necessarily hear thunder in the Pacific Northwest if it’s not a huge storm. She would catch little things.”

But there was one key scene from the book that Van Pelt advocated for keeping in the movie, involving the character Ethan (played by Colm Meany). Ethan runs the local town store and eventually strikes up the nerve to ask Tova on a date.

Tova’s friends inform her that if Ethan shows up to this “date” in a nice shirt, that means it’s romantic. So when Tova sees he’s wearing an old Grateful Dead T-shirt, she assumes this is just a friends thing. And she doesn’t feel too bad about accidentally spilling wine all over that shirt when she abruptly panics and ends the date early, either. After all, it’s just an old T-shirt… right?

In fact, it’s much more than old T-shirt. It’s Ethan’s prized possession. It’s a very rare T-shirt, worth a lot of money, that he usually keeps framed on his wall. The fact that he wore it on his date with Tova means he considered that a very special occasion. Obviously, Tova feels terrible. But at the end of the movie, she makes it up to him by returning the shirt to Ethan, clean. We can assume she used her formidable cleaning skills to get that wine stain out.

According to Newman, the moment where Tova returns the shirt to Ethan wasn’t going to be included in the movie, originally. But author Shelby Van Pelt insisted.

“She knew book fans really love that Tova returns the Grateful Dead t-shirt to Ethan at the end of the book,” Newman told Decider. “That had gotten lost for for a while during the drafts of the script. Shelby said, ‘You know, I think that they’re going to miss that, if we can’t get that back in.’ So we found a way to to bring that back in.”

It’s a very short moment at the end of the film, where Sally Field hands Colm Meany the clean shirt. But it ties up that story line, and lets audiences know Tova acknowledged how meaningful the shirt is to Ethan.

So even though the Remarkably Bright Creatures movie looks a little different than the Remarkably Bright Creatures book, fans can rest easy that Van Pelt made sure the scenes that were important to her, and to her readers, were included.

“Our goal was to maintain the DNA of the book and the characters, and make sure that those rang true,” Newman said.