Add Yahoo as a preferred source to see more of our stories on Google. Filet-O-Fish sandwich sitting on a white plate - Hanna Yohanna/Shutterstock There's something about a Filet-O-Fish, isn't there?

OAK BROOK, ILL. —McDonald’s Corp. has unleashed dolphins and sharks to promote the Filet-O-Fish and limited-time Double Filet-O-Fish sandwiches. The denizens of the deep actually are inhabiting ...