Keith Carradine Keith Carradine is the singer and actor who portrayed A . G . Robinson in the episode . Born in San Mateo , California , he is the son of ( 1906 – 1988 ) , the half - brother of ( 1936 – 2009 ) and the brother of ( born 1954 ) . Carradine ' s uniform from , including the boots , was sold off on the It ' s A Wrap ! sale and auction on eBay . Film career . Keith Carradine gained fame for winning an Academy Award and a Golden Globe for the song " I ' m Easy " , which he wrote and sang for director Robert Altman ' s 1975 film " Nashville " . Carradine even shared a Grammy Award nomination for Album of Best Original Score Written for a Motion Picture or Television Special . Carradine also starred in this film , along with fellow " Star Trek " performers Robert DoQui , Henry Gibson ( who was among those to share the Grammy nomination ) , and Bert Remsen . However , Carradine actually made his acting debut several years earlier as a cowboy in Altman ' s " McCabe & Mrs . Miller " , co - starring fellow " Trek " actors Rene Auberjonois , Robert Fortier , Bert Remsen , and John Schuck – all of whom were members of Altman ' s informal acting troupe . Four years later , Carradine was cast by Altman in the starring role of 1974 ' s " Thieves Like Us " . Other members of the Altman troupe returning for this film were Bert Remsen and John Schuck , while Louise Fletcher co - starred . Carradine worked alongside Fletcher again in 1996 ' s " 2 Days in the Valley " , which also starred Teri Hatcher and Lawrence Tierney . Carradine has many other notable films to his credit . In 1973 , he had a supporting role in Robert Aldrich ' s " Emperor of the North Pole " , along with fellow " Star Trek " alumni Hal Baylor , Elisha Cook , Jr . , Sid Haig , and Vic Tayback . That same year , he co - starred with Robert Walker in the drama " Hex " . In 1976 , he worked with Sally Kellerman in " Welcome to L . A . " , and the following year , he starred in ' s " The Duellists " , which also featured an appearance by W . Morgan Sheppard . In 1978 , Carradine starred in the drama " Pretty Baby " , co - starring Gerrit Graham . In 1980 , Carradine co - starred with brothers David and Robert in ' s acclaimed Western " The Long Riders " . Carradine would star in two more films from Walter Hill : 1981 ' s " Southern Comfort " and 1995 ' s " Wild Bill " ( the latter featuring Bill Bolender ) . He also starred in four films from director ( a protege of Robert Altman ) : 1984 ' s " Choose Me " with John Larroquette ; 1985 ' s " Trouble in Mind " with Albert Hall and Bill Smitrovich ; 1988 ' s " The Moderns " with Wallace Shawn and Geneviève Bujold ; and 1994 ' s " Mrs . Parker and the Vicion Circle " , also with Wallace Shawn as well as Matt Malloy and Mina Badie . Caradine ' s other films include the 1984 romantic drama " Maria ' s Lovers " ( co - starring John Savage and Bill Smitrovich ) , the 1995 thriller " The Tie That Binds " ( with Willie Garson , Barbara Tarbuck , and Ned Vaughn ) , and the 1997 drama " A Thousand Acres " ( with John Carroll Lynch , Kenneth Tigar , and Bob Gunton ) . His more recent film credits include 2001 ' s " Wooly Boys " ( with Rosanna DeSoto ) and 2002 ' s " The Angel Doll " , a Christmas movie in which he played the adult version of the character played by Michael Welch . In 2007 , Carradine starred in the western comedy " All Hat " , along with Stephen McHattie . In 2010 , Carradine joined the cast of " Cowboys & Aliens " , a sci - fi / western film scripted and produced by Alex Kurtzman , Roberto Orci , and Damon Lindelof . Fellow " Enterprise " guest star Clancy Brown also has a role in this film . Carradine wrapped his scenes for " Cowboys & Aliens " on 14 September 2010 . Television career . Carradine ' s numerous television roles range from his Emmy Award - nominated performance as Foxy Funderburke in the 1983 mini - series " Chiefs " ( co - starring Stephen Collins and Leon Rippy ) to his recurring role as " ' Wild Bill ' Hickock " on HBO ' s " Deadwood " ( starring Jim Beaver , Brad Dourif , Paula Malcomson , and Leon Rippy ) . He has worked on an extensive number of made - for - TV movies and TV pilots , as well . Three TV movies had Carradine acting with fellow " Enterprise " guest star Fionnula Flanagan : " The Godchild " ( 1974 , also featuring Ed Bakey , Ed Lauter , and Kermit Murdock ) , " Scorned and Swindled " ( 1984 ) , and " A Winner Never Quits " ( 1986 ) . In 1972 , Carradine worked with brother David as well as Keye Luke and Robert Ito in the pilot movie for " Kung Fu " . That same year , Joseph Sargent directed Carradine in an unsold pilot called " Man on a String " , which co - starred Byron Morrow , William Schallert , James B . Sikking , and Garry Walberg . In 1986 , Carradine starred alongside Saul Rubinek in the HBO film " Half a Lifetime " , which earned Carradine a CableACE Award nomination . His more recent TV movie credits include " Payoff " ( 1991 , with Lawrence Monoson and Jeff Corey ) , " In the Best of Families : Marriage , Pride & Madness " ( 1994 , with Ken Jenkins ) , " Special Report : Journey to Mars " ( 1996 , with Rosalind Chao , Deborah Lacey , and Alfre Woodard ) , " Hard Time : Hostage Hotel " ( 1999 , with Elizabeth Dennehy , Roy Jenson , Tony Plana , and Richard Riehle ) , and " Monte Walsh " ( 2003 , with Wallace Shawn and Marshall R . Teague ) . Carradine also co - starred with F . Murray Abraham , Brad Greenquist , and Jimmie F . Skaggs in the 1996 mini - series " Dead Man ' s Walk " , and in the following year , he and Duncan Regehr were regulars on the short - lived series " Fast Track " . Carradine more recently starred as Nick Savage on the TV sitcom " Complete Savages " , which lasted one season ( 2004 - 05 ) . He also appeared in the acclaimed Steven Spielberg - produced mini - series " Into the West " , as did Clayton Rohner , Keith Szarabajka , and ' s Garrett Wang . In 2007 and again in 2009 , Carradine played the recurring role of Special Agent Frank Lundy in the second and fourth seasons of the hit Showtime series " Dexter " . During his time on " Dexter " , Carradine worked with such performers as Tony Amendola , Jonathan Banks , Adrienne Barbeau , James Ingersoll , Don McManus , and Albie Selznick . Carradine also had a recurring role on the CBS series " Numb3rs " in 2008 . In 2009 , he had recurring roles on the Starz network series " Crash " ( working with Linda Park and Julie Warner ) and the short - lived Fox series " Dollhouse " ( including an episode directed by Jonathan Frakes ) . More recently , he played the recurring role of Julian Decker on the FX series " Damages " , on which he worked with Len Cariou and Wallace Shawn . Carradine played Wyatt , the father of Penny on " The Big Bang Theory " episodes " The Boyfriend Complexity " ( 2010 ) and " The Bachelor Party Corrosion " ( 2015 ) .