Mice love cheese, and Miss Mouse is no exception. In fact, she loves cheese so much that she uses it to build herself a brand new house. The only trouble is, the cheese does not love Miss Mouse. One morning she wakes up covered with spots from head to toe. To make matters worse, Miss Mouse discovers that she has swollen to an enormous size. What could be causing this strange condition? Fortunately, Doc Rat comes to the rescue. His diagnosis: mouse-cheese allergy! Doc Rat's prescription works like magic and soon all the spots and swelling disappear. The mystery solved, Miss Mouse can happily stay inside her beautiful new house of cheese.