Meet Ratio Holmes! He's not really the great, great grandson of the fictional character Sherlock Holmes, but all the other kids seem to think he is. Now he's a detective whether he likes it or not. Still, he's creative, good at thinking through facts, and has a wicked smart best friend, Jinju. Together, they might make great detectives after all! The school's holiday concert is at risk, fire alarms keep going off, and the kindergarten class's pet guinea pig is missing! There's a lot of chaos at Longtides Elementary. Can Ratio and Jinju find the cause and set everything back to the way it should be?