Arthur and his friends are challenged by Mr. Ratburn to come up with the perfect food for surviving on a desert island. Brain becomes suspicious about why Mr. Ratburn would give out such an easy assignment. When everyone brings in junk foods on presentation day, they discover it's not so easy, and must dive deeper for the perfect food - one that contains all the essential elements. Arthur, Francine and Buster think they have it figured out, but Brain is seemingly obsessed with the perfect food. (thetvdb.com)