Watch Sesame Street: A Magical Halloween Adventure for Free: How to Stream the Movie Online at 123Movies. . It's a Halloween extravaganza when the monsters from Sesame Street get invited to a Tricks & Treats party. But when Mumford the Magician has some trouble with his magic wand, Elmo and friends get sidetracked on a wonderful hayride. Share in the surprises as they learn to carve pumpkins, make scarecrows, and discover that monsters don't really have to be scary! Features special guest star Caroline Rhea as Gilda the Great!