As of season 5, five major actors from Game of Thrones have played villains on Strike Back: Charles Dance (Tywin Lannister) as Conrad Knox, Alexander Siddig (Doran Martel) as Zahir Sharq, Liam Cunningham (Ser Davos) as Daniel Connelly,Iain Glen (Ser Jorah) as Gerald Crawford and Michael McElhatton (Roose Bolton)as Oppenheimer.
At the end of the series, both Sullivan Stapleton and Phillip Winchester will star in two NBC shows in the fall of 2015. Sullivan will star in Blindspot, while Phillip stars in The Player with Wesley Snipes.
The trivia item below may give away important plot points.
Stonebridge and Scott are the only two members to survive Section 20. All previous team members are killed off throughout the seasons. Most not lasting more than 2 seasons.Martinez also survives, however she was never officially part of Section 20. Simply "On loan" from the DEA.