Jason Alexander in New York City on May 28, 2015.
Walter McBride—Getty Images
June 4, 2015

When George Costanza’s bride-to-be is killed off in an episode of Seinfeld, he was thrilled. Jason Alexander, the actor who played George, has admitted that the cast of the show was excited too.

“You know what? It’s f—ing impossible. It’s impossible,” Alexander told Howard Stern of the cast’s reactions to working with Heidi Swedberg, who played Susan.

Alexander stressed that he likes Swedberg personally, but that he “couldn’t figure out how to play off of her. Her instincts for doing a scene, where the comedy was, and mine were always misfiring. And she would do something, and I would go, ‘OK, I see what she’s going to do — I’m going to adjust to her.’ And I’d adjust, and then it would change.”

So one day Julia Louis-Dreyfus, who played Elaine, joked about killing Susan on the show. And Larry David, the show’s creator, decided to do just that. Susan met her demise licking toxic wedding invitation envelopes.

Listen to the clip below:

Read next: Hulu Announces When You Will Be Able to Stream Seinfeld

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Write to Tessa Berenson at tessa.berenson@time.com.

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