Favorite Sesame Street friends, peek-a-boo flap surprises, and adorably spooky Halloween fun make this book a good pick for boys and ghouls everywhere! It's Halloween and Elmo and his friends are all dressed up for trick-or-treating. Who is behind the puppy dog mask? Who is dressed as a pirate? Kids guess who and then find out if they are right when they open the peek-a-boo flaps on each page. Filled with Halloween surprises and delights, this book is spooktacular!