Bobby Aldridge Bobby Aldridge is a stuntman and stunt actor who appeared as an alien guard in the fourth season episode . He received no credit for his appearance but was identified by the name tag of his costume which was sold off on the It ' s A Wrap ! sale and auction on eBay where his name was misspelled as Bobby Aldrich . He filmed his scenes on Tuesday on location at the LA DWP Valley Generating Station and is listed as " Stunt Guard " on the call sheet . Aldridge performed stunts in several television series including episodes of " Hunter " ( 1989 , with Michael Canavan , Scott Jaeck , and Kathryn Graf ) , " The Adventures of Brisco County Jr . " ( 1993 , with Robert O ' Reilly and coordinated by Christopher Doyle ) , " Without a Trace " ( 2002 , with Enrique Murciano and Megan Gallagher , and coordinated by Dennis Madalone ) , " Six Feet Under " ( 2003 , with James Cromwell and Jim Beaver ) , " Deadwood " ( 2005 - 2006 , in several episodes alongside regulars Jim Beaver , Brad Dourif , Leon Rippy , Titus Welliver , and Allan Graf ) , and " Criminal Minds " ( 2007 , with Keith Carradine ) . Aldridge also performed stunts in feature films such as the science fiction sequel " Back to the Future Part III " ( 1990 , starring Christopher Lloyd ) , the action comedy " City Slickers " ( 1991 , with Noble Willingham and Tracey Walter ) , the science fiction sequel " Terminator 2 : Judgment Day " ( 1991 , with Earl Boen , Jenette Goldstein , Nikki Cox , and Joel Kramer ) , the comic adaptation " Batman Returns " ( 1992 ) , the comic adaptation " Tank Girl " ( 1995 , starring Lori Petty , Malcolm McDowell , and Iggy Pop ) , the comedy " Bean " ( 1997 , with Harris Yulin and Larry Drake ) , the science fiction remake " Planet of the Apes " ( 2001 ) , the comic adaptation " Spider - Man " ( 2002 , with Kirsten Dunst ) , and the action films " 2 Fast 2 Furious " ( 2003 ) and its sequel " The Fast and the Furious : Tokyo Drift " ( 2006 , directed by Justin Lin ) . Further credits as stunt performer include episodes of " Las Vegas " ( 2003 - 2007 , starring Nikki Cox and with stunts by Paul Eliopoulos ) , " Commanche Moon " ( 2008 , with Christina Weathersby ) , and " Knight Rider " ( 2008 , with Bruce Davison and stunts by Allan Graf , Paul Eliopoulos , Edward Conna , Antal Kalik , and Diana R . Lupo ) , the crime drama " Appaloosa " ( 2008 , with Mark DeAlessandro and coordinated by Mike Watson ) , Justin Lin ' s action sequel " Fast & Furious " ( 2009 , with Dwayne Johnson ) , the comedy " Year One " ( 2009 , with Trace Cheramie , Derek Graf , Bobby C . King , Carrick O ' Quinn , and Boni Yanagisawa ) , the comic adaptation " The Green Hornet " ( 2011 , with Eddie Braun , Jay Caputo , Jennifer Caputo , Yoshio Iizuka , Hiro Koda , Brian Avery , Hunter Baxley , Dana Dru Evenson , Kevin Derr , Anita Hart , Matt McColm , and Dorenda Moore ) , the science fiction thriller " Cowboys & Aliens " ( 2011 , written by Roberto Orci , Alex Kurtzman , and Damon Lindelof ) , and the crime drama " Gangster Squad " ( 2013 , coordinated by Doug Coleman ) . As stunt coordinator , Aldridge worked on the short projects " Confidence " ( 2007 ) , " Defiance " ( 2008 ) , " Propaganda " ( 2008 ) , " View from the Top " ( 2011 ) , " Blowback " ( 2013 ) , and " The Mad Seasons of Alexine " ( 2014 ) and the drama " The Portrait ' s Secret " ( 2018 ) .