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John Travolta is a real life actor who played the part of Danny Zuko in the movie Grease. He makes a cameo appearance in the story Cheese Is The Word by Kemical Reaxion, which is a parody of that movie. In this story, Brittany drops out of high school to become a Dallas Cowboys cheerleader but discovers that it's not all it's cracked up to be. After she quits the Dallas cheerleading squad, she is riddled with self-doubt and is unsure what she should do next. John Travolta appears to her in the form of a snarky guardian angel in a polyester leisure suit. He sings the song "Cheerleader Burnout" to Brittany to help her make a decision about her future, suggesting that she give up on being a cheerleader and go back to school. The song is a parody of "Beauty School Drop-out," a song performed by Frankie Avalon in the movie Grease.