The principal has promised to read aloud from the school's roof if the students read 1000 books during their reading marathon. When he agrees to read a story by Fletcher's owner Gwen, she is thrilled--until the principal starts sneezing uncontrollably as he's reading her science fiction story about aliens who live on rooftops and make humans sneeze! Can Fletcher and Jasper solve the mystery before the principal falls off the roof and Gwen gets blamed?