Initially a cult success before becoming one of British television's most watched programmes, Callan brought the gritty, downbeat angle of Cold War espionage to 1960s British television. In stark contrast to the glamour of James Bond and the stylized capers of The Avengers, the man known as David Callan was a highly skilled killer, tasked by the Government to eliminate threats to national security. This reluctant, conscience-wracked assassin was brought to life in a remarkable performance by Edward Woodward, cementing his popularity as an actor many years before he achieved major international success in both Breaker Morant and The Equalizer. This exhaustive book is the definitive look at the creation, production, broadcast and reception of all four series. From its conception as a one-off BBC play, through its development by ABC Television, its success as one of Thames Television's highest-rated programmes, its subsequent ATV revival and its expansion into novels, short stories and movies - this single volume covers every aspect of James Mitchell's most successful creation.