Deep Six is a series of books written by Timothy McGee, under the pseudonym Thom E. Gemcity, in his spare time.

There are currently two books in the series:

The characters are based on the agents in McGee's squad: "L.J. Tibbs" is based on Leroy Jethro Gibbs; "Lisa" is based on Ziva David; "Tommy" is based on Anthony DiNozzo; "Amy Sutton" is based on Abigail Sciuto; "Pimmy Jalmer" is based on Jimmy Palmer;  and "McGregor" is based on McGee himself with the plot lines inspired by cases the team worked on.