Mark Harmon

as Ryan

as Older Leroy Jethro Gibbs (voice) (uncredited)(36 eps)

as Older Leroy Jethro Gibbs(10 eps)

as Self

as Self - Narrator (voice)(6 eps)

as Self(1 ep)

as Self

as Narrator (voice)(8 eps)

as Self(8 eps)

as Self - Guest(1 ep)

as Self(1 ep)

as Leroy Jethro Gibbs(4 eps)

as Self(1 ep)

as Self(1 ep)

as Lucas Davenport

as Superman (voice)

as Dale

as Self(1 ep)

as Self(1 ep)

as Self - Guest(1 ep)

as Self(1 ep)

as James Foster

as Leroy Jethro Gibbs(435 eps)

as Ryan

as Self(1 ep)

as Jim Wesley

as Self

as Bob Markham (voice)(1 ep)

as Thomas Capano

as Thomas Capano(2 eps)

as Bruce Barkow

as Lawrence

as Charles Lattimer

as Simon Donovan(4 eps)

as John Cooper

as Leroy Jethro Gibbs (voice)(1 ep)

as Magazine Reporter

as Wally Schirra(1 ep)

as Self(1 ep)

as Tommy Nance

as Jeremy Hampton

as Self(1 ep)

as Mark(1 ep)

as Leroy Jethro Gibbs(2 eps)

as Charlie Grace(9 eps)

as Dominant Male

as Jack Black

as Johnathan Franye

as Jack McNeil(96 eps)

as Mickey Knox in TV

as Sheriff Johnny Behan

as Alex Davenport

as Det. Dicky Cobb(44 eps)

as Frank Flynn

as Charles Spencer

as Ertie Robertson

as David Shepard

as John Dillinger

as Taylor Worth

as Chance Wayne

as Billy Wyatt

as Jay Austin

as Elmer Jackson

as (voice)

as Freddy Shoop

as Harry

as Ted Bundy

as Ted Bundy(2 eps)

as Robin Prince

as Sam Crawford(4 eps)

as Gacel Sayah

as Tommy

as Robert Caldwell(59 eps)

as Peter Cabot(2 eps)

as Self(1 ep)

as Field Carlyle(37 eps)

as Fielding Carlyle

as Johnny Edge(3 eps)

as Thib Thibideaux(13 eps)

as Larry Simpson

as Billy Joe Meynert

as Captain John McIntosh(12 eps)

as Norman Brinker

as Howie Lesser

as Mike Breen(6 eps)

as Doug Bradbury(3 eps)

as Robert Dunlap

as Ronnie Striker(1 ep)

as Victor(1 ep)

as Self - Host(1 ep)

as Stanski(1 ep)

as Paul Donin(1 ep)

as Student Controller

as Ofcr. Dave Gordon(1 ep)

as Officer Gus Corbin(1 ep)

as Self(1 ep)

as Charles(1 ep)

as Self - Nominee(3 eps)

as Self(1 ep)