A mysterious alien substance copies Ben's appearance and powers while Ben is visiting a space museum, and quickly assumes the shape of other people, leaving the Tennysons to find a way to reveal who is actually the mysterious substance. Note: This episode is a parody of The Thing.
Casts:
Tara Strong, Montse Hernandez, David Kaye, Roger Craig Smith, Josh Keaton, John DiMaggio, Daryl Sabara, Travis Willingham