Over the past 60 years Britain's Special Air Service regiment has carried out a wide variety of clandestine missions - from deep-penetration raiding to hostage release operations - which have made it respected and feared for its professionalism and daring. The SAS prides itself on doing its work in the shadows, never allowing any publicity and never claiming credit for any of its extraordinary achievements. But, over the years, sufficient information has emerged for a picture of the regiment's exploits to be clear. This series uses interviews with former members of the SAS; detailed and painstaking reconstructions; and cutting edge 3-D graphics to recreate seven great missions which show why the SAS is today regarded as the world's leading special forces unit..