'Catastrophe' Star and Writer Rob Delaney Remembers His TV Mom Carrie Fisher: She Was 'So Brilliant'

Fisher died on Tuesday after going into cardiac arrest last week.

Rob Delaney is remembering his Catastrophe co-star, Carrie Fisher.

The 39-year-old actor opened up about acting alongside Fisher in a hilarious and heartwarming piece published in The Guardian on Wednesday, in which he describes writing extra scenes to accommodate his brilliantly funny co-star, and his lifelong admiration and love for her.

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Fisher died on Tuesday after going into cardiac arrest last week during a flight from London to Los Angeles. She was in the U.K. filming scenes for Delaney's Amazon series, Catastrophe. 

"Yes, I knew Carrie Fisher. She played my mom on Catastrophe, the sitcom I write and star in with Sharon Horgan. Or should I say, 'plays my mom,' since we just finished shooting last week and Carrie's scenes haven't been seen by anyone yet. Except for me and Sharon that is, and our director, producer and editor," Delaney wrote. "We've seen them and they're amazing. I played some early cuts for my dad the other day and he was roaring. She's a bigger part of series three than she was of the first two series. We couldn’t help but write more for her because she's so brilliant."

"So yes, I knew her, but like you, I was a fan first and a fan forever. Don't feel worse for me today than you feel for yourself. Actually feel a little bit worse for me, since I won't get to have her act right into my face any more or goof around with her between takes," he added.

"Carrie was the only cast member Sharon and I would let improvise. (I say 'let'; as if we could stop her. She let us put her in our show.) We're a bit despotic and inflexible with our dialogue because we're insane, but Carrie was more insane and would always, always make it funnier and better," he explained. "In episode one of series two you can hear her singing an improvised song about areolae in the background of our daughter's christening party."

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While Delaney couldn't get enough of Fisher's humor on their show, his love for the actress began much earlier, as he describes admiring how "beautiful" she was while trying to "violently murder" Jake and Elwood in The Blues Brothers.

"I spent my teenage years fantasizing about a shiny-lipped Carrie Fisher trying to murder me and my fugitive brother one day … So naturally I tried to seduce Carrie when we finally did work together, especially after Variety called me 'the poor man's Harrison Ford, who is also fat,'" he recalled. "I'd like to report that I was successful, but despite my begging her on many occasions, we never had sex, even though our onscreen mother/son chemistry was off the charts."

"We made her and Adam Driver's sterile scenes in The Force Awakens look like bank transactions. Adam, if you’re reading this, you might want to consider spending some of your Star Wars money on acting lessons instead of Lamborghinis," he joked.

"What I'm getting at here is that I revered Carrie until I met her and then I loved her. I'm smiling thinking about her," he concluded. "I hope you are too."

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ET caught up with Delaney and Horgan earlier this year, where they gushed about having Fisher on set. 

"We're also very in love with Carrie Fisher so we always try and think of how we can get her in it more," Horgan explained. "Obviously, heading back to Rob's hometown would give us more time with her. Hopefully, at some point it'll happen."

See Horgan's sweet tribute to Fisher, and more about the actress' final days in London, in the video below.