Actor Shia LaBeouf at the Berlin premiere of “Transformers: Dark of the Moon.” Presumably, he was not listening to Feist when this photo was taken. (Markus Schreiber/AP)

Shia LaBeouf appeared on “The Late Show With David Letterman” Monday night and fielded some tough questions about working on “Transformers: Dark of the Moon.”

For one, he had to explain to Letterman that Rosie Huntington-Whiteley did not, technically, replace Megan Fox in the movie, because the Victoria’s Secret model plays a new character. (LaBeouf managed to keep from laughing during this explanation, but it was a close call.)

He also discussed the directorial style of Michael Bay, who he called “an aggressive guy, hard to work for, demanding.” LaBeouf then revealed that he used the song “Brandy Alexander” by Feist to get in a weepy mood during a particular scene in the film, a track that the “aggressive” Bay didn’t entirely embrace.

How did they work it out? Let’s let Mr. LaBeouf explain.