【The Lord of the G-Strings: The Femaleship of the String】

Of this much,The Lord of the G-Strings: The Femaleship of the String I'm sure: Carrie Fisher was nothing short of a legend.

That's why it was of little surprise to learn that she was a bit of a rule-breaker during her time filming Catastrophe.

Sharon Horgan and Rob Delaney — who both write and star in the series — told Mashable during an exclusive screening of Season Four that they were protective over the final script and didn't allow cast members to improvise any lines. Except, of course, for Carrie Fisher.

Delaney said that Fisher would "improvise ferociously." "It was scary at first but then we knew to prepare for it," he said.

Horgan revealed what happened during the first scene she and Fisher ever filmed together.

"The first scene she ever did, it was just me and her talking on the phone and I'm supposed to be inviting her to our wedding and we ended up, in the scene, just insulting each other and putting the phone down," said Horgan. "We just went at each other. This is the first time we'd met, and she definitely called me a cunt. Yep it was ferocious."

Delaney said that both he and Horgan did a "phone scene" with Fisher, which resulted in "maybe 50 seconds of film." But, the duration of the clip that made it into the final cut actually took a lot longer to film.

"We were on the phone each of us for 45 minutes just screaming. It was awesome," said Delaney.

Horgan said that Fisher was "a joy to be around" and "exactly what you'd expect."

"Someone you'd want to sit around and listen to. She was really open about her interesting Hollywood upbringing, and she was really open about her addictions," she said.

"We really got to know her in the 3rd series, and that's extra why it hurt, because we really got the feeling that this is someone I'm gonna spend a lot of time with," Horgan continued.

To be fair, being called the c-word by Carrie Fisher is a unique honour.