The shots of the submarine under water and of the emergency blow, as well as the landing of the helicopter, are from The Hunt for Red October (1990). They were all performed by the USS Blueback, which was eventually retired to serve as a stationary exhibit at OMSI (Oregon Museum of Science & Industry) in Portland, Oregon.
Special Agent Timothy McGee was first introduced in this episode.
First appearance of Tony in a suit, which became his trademark style of dress.
This is the first appearance of Sean Murray. He previously appeared on JAG (1995) as Danny Walden in five episodes and as Ensign Terry Guitry in one episode, which is the series that NCIS (2003) is a spin-off of. He is also the stepson of both series' creator Donald P. Bellisario.
When asked how he can drink coffee in triple-digit heat with no air conditioning, Gibbs's retort that it keeps him cool is biologically sound; the hot beverage will cause him to sweat, which, as it evaporates, helps lower his body temperature.