Colin Singleton is a prodigy. Not a genius, just a prodigy. And now that he's eighteen and graduated from high school, his prodigy status has expired - and Colin's certain he'll never make it to genius.

When Colin's girlfriend - Kathrine XIX (the 19th in an amazing line of Katherines he has dated) dumps him, Colin's best friend Hassan convinces him to take a road trip. In Gutshot Tennessee, Colin and Hassan discover the grave of an Austrian archduke and the Theory of Underlying Katherine Predictability, which Colin thinks will prevent future heartbreak by all women named Katherine.

Is Colin a dumpee, or is he really a dumper at heart? Will he ever make "genius" - will he ever really matter? And what's with all the Katherines, anyway?

Not all teens will appreciate John Green's hilarious novel - some might find Colin just as annoying as his classmates do. Other's will see themselves in Colin's social ineptitude and his unluckiness in love. As with Looking for Alaska, Green has created a truly clever cast of characters and a truly clever book. Instead of Pudge's last words, this time he gives us Colin's anagrams, and, of course, his Theory of Underlying Katherine Predictability - complete with footnotes and a mathematical explanation of the formula (written by a real mathematician - see Appendix A).