The movie had a dead cat problem.

As the director Marielle Heller prepared to shoot “Can You Ever Forgive Me?,” a biopic about the literary forger Lee Israel, she knew that she would need a highly realistic prop to pull off the pivotal scene where Israel finds her beloved pet cat, Jersey, dead. Heller wanted a dead cat with heft. She wanted an inanimate object that her star, Melissa McCarthy, could act against. “I was really intense about it,” Heller said over the phone recently. “We discussed strategy a number of times.”

So important was the dead cat that Heller sought to secure it even before casting the film’s real live Jersey. She’d just find a feline that looked like her wonderful prop. How much difference could the real one make, anyway? On her first film, “The Diary of a Teenage Girl,” she had saved money by tossing her own cat, Willie, in front of the camera. So when the movie’s animal trainer promised to bring in what she called her highest-performing cat, Heller wasn’t sure what that could mean. That it wasn’t going to pee everywhere?

The cat’s name was Towne. He was a lanky black and white guy with green eyes and a petal pink nose, and to everyone’s surprise, he was amazing . Yes, he followed directions — hitting his marks with the help of a trainer equipped with a clicker and a laser pointer — but he also seemed to do something more. “Towne had a very expressive face,” Heller said.

There is a moment in the film where he gazes toward McCarthy “sort of sympathetically, and also judgmentally, and you feel all of that,” she added. Heller ended up commissioning a prop modeled after Towne that cost thousands of dollars — the most expensive one for the production.