Phillippe Legorjus was the Chef d'Escadron of the GIGN (equivalent to a major or colonel) and was the overall head of the GIGN from 1983 to 1989. (He is referred to as a Captain in the subtitles of the Australian DVD.) Christian Prouteau, who is Legorjus' contact in Paris, was a previous head of the GIGN and was its founding commander from 1973-1982.
The GIGN is the Groupe d'intervention de la Gendarmerie nationale ("National Gendarmerie Intervention Group"). It is a special operations unit of the French National Gendarmerie, set up in 1973 after the massacre at the MunIch Olympic Games.
The units, other than the GIGN, that were involved in the attack were Commando Hubert (a 'Commandos Marine' unit of the French Navy) and 11e régiment parachutiste de choc (an elite parachute unit, part of the Directorate-General for External Security).