Strange Attractors

Recent high school graduate Max is looking forward to his visit to Mercury Labs, an honor for top science students, when his mother tells him he's already been there--yesterday. Then Eve, the daughter of the Lab's top scientist, Dr. Sylvan, calls Max and asks him to return what he took from the Lab. But Max doesn't remember anything at all, and discovers that there are two Eves and two Dr. Sylvans. Which ones are real and which are imposters? What does Dr. Sylvan's work on the chaotic bifurcation graph have to do with time travel? - Publishers Weekly