ALA Booklist

Thirteen-year-old Carson Fender, aka Agent Zero, finds school and even pulling pranks dull after his stint as a secret agent a few months prior. As if in response to this ennui, Carson is pulled from retirement to infiltrate a secret lab hidden in the depths of Mount Rushmore and save a fellow agent. This mission, however, is just the tip of the iceberg, as double-crossings and a deadly virus pit Carson against the clock and put the fate of the world in his hands once more. Second in the Codename Conspiracy series, this book is packed with laughs, gadgets, and close shaves.

School Library Journal (Sun Mar 01 00:00:00 CST 2015)

Gr 6-8 This sequel to Codename Zero finds former kid agent Carson Fender back in the civilian world. After foiling the dastardly villain and his terrorist plot, Carson is happily spending his days as a normal, carefree middle schooler. But when he learns about another potential mole and that one agent's life is in danger, he finds himself back in the wild world he'd left behind. A fun series for readers who enjoy James Bond-esque thrill rides.

Horn Book (Sat Aug 01 00:00:00 CDT 2015)

When Agent Nineteen's life is threatened by a deadly virus that's fallen into enemy hands, ex-spy Carson (Codename Zero) is tasked with breaking into a secret lab inside of Mt. Rushmore to save the day--while on a school field trip. Action-packed and humorous, this installment adds interesting character development as things get more serious and Carson struggles with some realistic moral dilemmas.