There are some Christmas movies that we can watch every holiday season, again and again, without fail.

From Home Alone to Die Hard (which totally is a Christmas movie) and everything in between, the festive classics just never get old. However, we'll always have a soft spot in our hearts for Elf. The comedy, which was released 15 years ago, stars Will Ferrell as Buddy the elf, a human who was raised by Santa's helpers. But after he grows too big for his home, Buddy goes on an adventure to find out everything he can about his real family. Ferrell recently spoke to Rotten Tomatoes about the film, including the iconic line he improvised and the one part of the movie that makes him cry. And, pretty unsurprisingly, it is one of the emotional moments in the entire movie. He explained:

"That moment where Buddy is in the back of the sleigh and everyone's singing in Central Park and there's enough Christmas spirit to get it lifted off, and he's waving goodbye. "I'm like, 'Oh, I can't let everyone see me cry here at my own movie."

The 51-year-old also revealed that one of the most memorable lines from the film, Buddy's 'Santa! I know him!' before St. Nick arrives in Gimble's, was actually an improvisation. He added that while "the first couple of takes really took people by surprise", the line was meant to capture Buddy's infectious joy over seeing a familiar face. He continued:

"That was just my articulation of Buddy literally taking that piece of news at face value and [thinking] what would be his literal reaction. "A man without a country in this strange land finally getting to see someone he knows really well - it would be the most jubilant reaction ever."