What happens when the boys accidentally knock a UFO off its course, causing it to crash in their backyard? And when will they meet its pilot, the adorable Meap? and It's all fun and games when Phineas and Ferb create a swimming pool full of gelatin...until Dr. Doofenshmirtz's latest creation brings it to life! Phineas and Ferb have to find a way to stop the giant gelatin monster and save Candace.