When Tony opens a mysterious letter thinking it's for him, a small puff of white powder comes out and releases a possible deadly virus. Soon Kate and Tony are isolated in a bio-hazard isolation room for precaution. McGee and Gibbs work to discover who sent the envelope and how to cure their friends before it's too late for them.
as Leroy Jethro Gibbs
as Timothy McGee
as Tony DiNozzo
as Caitlin Todd
as Dr. Donald 'Ducky' Mallard
as Abby Sciuto
as Jimmy Palmer
as Sarah Lowell
as Cassie Yates
as Hanna Lowell
