The ‘Christmas Vacation’ Cast Improvised These 3 Memorable Moments

The popular holiday movie, National Lampoon’s Christmas Vacation, is filled with quotable lines and memorable moments. And some of them weren’t in the script written by filmmaker John Hughes

Clark Griswold’s mom greeting him with a knock-knock joke greeting

Chevy Chase as Clark Griswold in 'National Lampoon's Christmas Vacation'
Chevy Chase as Clark Griswold in ‘National Lampoon’s Christmas Vacation’ | Warner Brothers/Getty Images

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Chaos ensues when the parents of Clark Griswold (Chevy Chase) and Ellen Griswold (Beverly D’Angelo) arrive at their house. There’s a flurry of greetings, one of which involves Clark’s mother, Nora, doing a unique knock-knock joke with her son. 

Diane Ladd, the actor who played Chase’s on-screen mom in the film, revealed in a 2014 interview with Rolling Stone she came up with the knock-knock joke herself. It’s something she did at her audition and a version of it made the final cut of Christmas Vacation

“I marched right over to Chevy and I grabbed his face, pulled open his mouth and played a game: ‘Knock-knock, who’s there?’ That was improvised and something like it wound up in the movie,” Ladd said. 

RELATED: National Lampoon’s Vacationing Griswold Family is Getting a TV Spinoff

Cousin Eddie saying ‘bingo’ in the sledding scene

Although Christmas Vacation is set in Chicago, Illinois, the movie was actually filmed in California on the Warner Bros. lot and in Breckenridge, Colorado. While shooting the sledding scene in Colorado, Randy Quaid improvised one of Cousin Eddie’s short but memorable lines. 

In the same Rolling Stone interview, Ellen Latzen, the actor who played Cousin Eddie and Cousin Catherine’s (Miriam Flynn) daughter, Ruby Sue, shared a line Quaid improvised.

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She recalled him saying “bingo” after Clark went down the hill at warp speed before ending up in a Wal-Mart parking lot. 

“I remember at the end of the scene, Randy Quaid’s line ‘Bingo’ was totally improvised,” she said. “[Director] Jeremiah Chechik said, ‘That was amazing, say that again!’”

The scene also features some of Christmas Vacation’s other famous quotes from Cousin Eddie, including comments about his hair and the metal plate in his head. 

Ellen Griswold putting her hand on Clark Griswold’s crotch

Reflecting on Christmas Vacation with some of her co-stars for Rolling Stone, D’Angelo pointed out a small detail in one of the movie’s final scenes. When the police show up to the Griswold house and tell everyone to freeze, Ellen puts her hand on Clark’s crotch. The move wasn’t included in the script but rather D’Angelo’s idea. 

“Did you catch when the police came in and there’s a freeze-frame where my hand was (on Chevy’s crotch)? I did that spur of the moment and told Chevy, just to see if anyone on set noticed,” she said. “But we did a couple takes and no one mentioned it.”

In the same scene, D’Angelo’s character shakes hands with Frank Shirley’s (Brian Doyle Murray) wife, Helen (Natalia Nogulich), before putting her hand back.  

Christmas Vacation isn’t on Netflix at the time of publication. But not to worry. Fans of the Griswold family can watch them celebrate Christmas by watching Christmas Vacation on TV.

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