Commander in Chief (stylized as Tom Clancy Commander in Chief, Tom Clancy: Commander in Chief, or Tom Clancy’s Commander-in-Chief in the United Kingdom) is a political thriller novel, written by Mark Greaney and released on December 1, 2015. In the book, President Jack Ryan and The Campus must stop Russian president Valeri Volodin from launching a covert violent offensive in an effort to bring back Russia as a superpower. Commander in Chief is Greaney’s third solo entry in the Jack Ryan series, which is part of the overall Tom Clancy universe. The book debuted at number two on the New York Times bestseller list.