Justin Timberlake offered to appear in 'Candy' because producers didn't have "any money left" to hire another big name

Jessica, who also serves as ex ecutive producer on the show, said: "I always ask him for his opinion on everything I'm doing.

"He said, 'Oh, who's playing this character?' I said, 'Oh, I don't know, probably somebody local. We don't have any money left.' And he goes, 'I want to play it.' "

Jason Ritter also had a surprise role as Justin's police partner and his wife Melanie Lynskey - who portrays victim Betty - explained showrunner Robin Veith was inspired to cast him after seeing a photo of him with a moustache.

She said: "Robin was like, 'Wow, Jason looks like he's in the '80s.' She was inspired by his '80s cool, edgy fireman look. [But] he had to lose the stache anyway."

The actresses were impressed with the "amazing" chemistry their husbands had, and their on-screen partnership has led to a new friendship.

Jessica told 'Entertainment Tonight': "They were so brilliant together. Clearly, Jason is a comedic genius and Justin is in his own right as well. And the way they work off each other and the improv that they did, it was amazing to see.

"The two of them had become besties. It was pretty endearing."

Melanie added: "They text all the time [and] had a lot of discussion about their character. Also, there were long phone calls."

The rest of the cast welcomed the addition of the celebrity husbands to the show.

Pablo Schreiber, who plays Betty's husband, Allan, said: "The Justin news came first and I thought that was so cool. Obviously, he's going to bring a certain interest to the project from his own fan base.

"And just to have people that are married getting to work together and on the same set, it's like a big family.

"It felt like we were a little bit of a repertory theatre company or something, you know, with all the husbands and wives showing up to support. And that was amazing. So, I was really happy when the casting came out."