Strike Back is a military television series that blends elements of action, thriller, and drama. The show is primarily concerned with the acts of secretive branch Section 20. As a branch of the British Defence Intelligence service, Section 20 members execute several high risk missions throughout the world. The characters of Strike Back give the series shape and color. For example, the story's central character emerges as an individual who has resigned from the SAS after an Iraq rescue mission which took place prior to a 2003 American-led invasion. Strike Back is rife with a variety of themes, including jealousy, war, violence, and betrayal.