Watching Mark Harmon in all the movies and tv series he did over the years, made me notice his habit of dragging former co-stars to new projects of his. Just in case you're wondering where you have seen one or the other co-star you might take a look at this list. It's nowhere near complete. If you have someone to add feel free to drop me a line.

NameTV Series/ MovieNotes
Adam ArkinChicago Hope | The West Wing
Alicia CoppolaChicago Hope | JAG | NCIS
Annabeth GishChicago Hope | The Last Supper | Wyatt Earp
Anthony HealdBoston Public | NCISThe pre-NCIS collab-oration between MH and AH was more like director-actor. MH directed two episodes of Boston Public.
Charles DurningNCIS | The Last Supper
Chris EllisChicago Hope | From The Earth To The Moon | NCIS
Corin NemecNCIS | The First To Go
Cristina RainesCentennial | Flamingo Road | LoveBoat
Cynthia SikesFlamingo Road | St. Elsewhere
A - C | D - I | J - O | P - R | S - Z