Devlin is a twelve-year-old girl, who lives at home with her mother, and her best friend Liza who recently moved in with them. She lives in New York City and attends Ditchley School. Devlin is very brave curious and intelligent, because she will investigate or look into anything that is questionable even if it is risky or dangerous. Many readers will compare Devlin to Nancy Drew because she is very good at uncovering mysteries. Devlin is a great friend to Liza,and never lets her down. Liza can always trust Dev with anything, because they are so close. Throughout the novel, any reader will see how courageous and brave Devlin is.
Liza is an Argentinian student who'd gotten a scholarship to "the Ditch" (as Dev would call it) for the summer and is staying with Dev and her mother. Liza comes to New York in a neon orange and pink tee shirt, with temporary glasses, and braces. Liza is extremely intelligent, and she is very precise. Liza loves reading, in fact Dev calls her a "bookworm" throughout the novel, and she loves mysteries or problems just like Dev.
Booker has been best friends with Devlin for many years, and he acts like Devlin's older brother. He is six months older than Devlin, he is thirteen in the novel. Booker goes to a school called Hunter, with his brothers. Both of his parents are doctors, and Booker wants to be a doctor when he is older. Booker is just like Liza, very smart, and he is compassionate. Whenever Devlin needs help with anything she always calls Booker, for advice, or help. Booker helps Liza and Devlin uncover the case, and without him, it would not be possible.