David Duchovny
Agent Fox Mulder
Gillian Anderson
Agent Dana Scully
Mitch Pileggi
Assistant Director Walter Skinner
William B. Davis
The Cigarette-Smoking Man
John Neville
The Well-Manicured Man
Martin Landau
Kurtzweil
Jeffrey DeMunn
Bronschweig
Tom Braidwood
Frohike
Blythe Danner
Cassidy
Terry O'Quinn
Michaud
Dean Haglund
Langly
Bruce Harwood
Byers
Armin Mueller-Stahl
Strughold
Lucas Black
Stevie
Christopher Fennell
2nd Boy
Cody Newton
3rd Boy
Blake Stokes
4th Boy
Don S. Williams
Group Elder
George Murdock
2nd Elder
Michael Shamus Wiles
Black-Haired Man
Darrell Davis
Primitive #1
Carrick O'Quinn
Primitive #2
Tom Woodruff Jr.
Creature #1
Greg Ballora
Creature #2
Ted King
FBI Agent on Roof
Luis Beckford
FBI Agent
Steve Rankin
Field Agent
Gary Grubbs
Fire Captain Cooles
Steven M. Gagnon
Last Agent Out
Larry Joshua
DC Cop
Glendon Rich
DC Cop #2
Gunther Jenson
Security Guard
Scott Alan Smith
Technician
Ian Ruskin
Well-Manicured Man's Valet
Paul Welterlen
Control Room Operator
Joel Traywick
Young Naval Guard
Milton Johns
British Valet
Michael Krawic
2nd Paramedic
Larry Rippenkroeger
Towncar Driver
Josh McLaglen
Buzz Mihoe
Randy Hall
Windbreakered Agent
T.C. Badalato
Fireman
Amine Zary
Tunisian
David Paris
Pilot
Vanessa Morley
Young Samantha Mulder (archive footage)
Jason Beghe
FBI Man at Bomb Site (uncredited)
Glenne Headly
Barmaid