In Harry Potter, Tom Riddle's diary was filled with Riddle's secrets and memories. Now, fill it with yours! Using the magical quill, write your inner thoughts and clever plans in invisible ink. Then shine your wand's UV tip on the page to reveal what you've written! This wonderful set includes the replica of Tom Riddle diary, an invisible-ink pen, and a UV wand. Comes complete with three AG10 batteries that power the UV light.