The Harry Potter actress appears in the new movie alongside Logan Lerman and Ezra Miller, and to cure their boredom in between takes, they penned tracks and performed sets, calling themselves Octopus Jam.
Watson says, “Throughout the movie we all made music together. Our band was called Octopus Jam. I sing and Logan Lerman is a classical composer, and he created a piece for me. Most nights we would sit and play music, so that was fun.”