George is getting upset.

George Costanza from “Seinfeld.”

I 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. …. It’s fucking impossible. It’s impossible! And Julia [Louis-Dreyfus] actually said, ‘I know. Don’t you just want to kill her?’ And Larry went, ‘Kabang! … We’ve got to kill her.’

Jason Alexander (Seinfeld’s George Costanza), speaking to Howard Stern re. working with Heidi Swedberg, who played George’s fiancée Susan on the show.

Telling this story on the air was a mistake for Jason Alexander. Two reasons:

First, it’s in poor taste to bad-mouth a guest star on the show that made you rich. You’re (still) one of the most recognizable faces in comedy. She now teaches ukelele to grade school kids and hardly has a platform to defend herself. Plus, Alexander admits that he helped get her written off the show. Why share an anecdote that makes you sound like a jerk?

A second reason why Alexander gets this wrong? Maybe the lack of chemistry made their scenes work better. The audience can sense that George genuinely dreads every interaction with Susan. She makes Costanza—or maybe Jason Alexander himself—ooze discontent.

Heck, for all we know, maybe the actress intentionally made Alexander squirm, just to squeeze out those reactions from him.

UPDATE (6/4/15): Jason Alexander seems to agree that making these comments was a mistake. He posted an apology to Heidi Swedberg on his Twitter account. Here’s an excerpt:

She was generous and gracious and I am so mad at myself for retelling this story in any way that would diminish her. If I had had more maturity or more security in my own work, I surely would have taken her query and possibly tried to adjust the scenes with her. She surely offered. But, I didn’t have that maturity or security. And, Larry [David] and Jerry [Seinfeld] would probably have killed me as it was all playing exactly as they wanted. Clearly Susan and George were coming off just the way they wanted.