Charles Edward Eppes, Ph.D., is a fictional character and one of the protagonists of the CBS crime drama Numb3rs. He is portrayed by David Krumholtz. Eppes is portrayed as a young mathematical genius and professor of applied mathematics at the fictional California Institute of Science, CalSci (primarily based on Caltech, where some filming and mathematics consulting is done). As a world-class mathematician, Charlie helps his brother Don Eppes solve many of his perplexing FBI cases, sometimes with the help of his best friend, mentor and colleague Larry Fleinhardt, and his on-again/off-again girlfriend, former student and now wife, Amita Ramanujan, who further refines Charlie's approach and helps him stay focused. Charlie has consulted for the National Security Agency (NSA), in part as a cryptanalyst, for nearly five years, having attained TS/SCI security clearance. It was revoked at the end of season four after he transmitted information to Pakistan, but was later re-instated. Backstory According to Eppes' father, he could multiply four-digit numbers mentally at age three and at the age of four required special teachers. In the second grade, he attempted to find a 70-digit narcissistic number in base 12—Eppes has described himself as "quixotic" in elementary school. A prodigy, he attended Princeton University at the age of 13 after graduating from high school at the same time as his brother who is five years his senior ("Soft Target"), and took Professor Lawrence Fleinhardt's quantum physics course in his first year. They became fast friends, with Fleinhardt establishing his academic connections. Eppes published his first mathematical treatise at the age of 14 (in the American Journal of Mathematics) and graduated at the age of 16. In fact, he was the youngest person to ever write a paper of importance. It was his paper on the Eppes Convergence, which concerned asymptotics of Hermitian random matrices, that made him a star in his field. Following a seminar that heavily criticized this seminal piece many years after its initial publication, Charlie realized that his work with the FBI has prevented him from doing research significant to other mathematicians and now hopes to spend decades on cognitive emergence theory ("the mathematics of the brain") to rectify this certain inequity, which has delighted Fleinhardt. Although he was a child prodigy, Charlie now laments the fact that his best years in his research will never come ahead of schedule again. Eppes is a multiple Ph.D. ("Decoy Effect"),