The best known and most successful Lions team was that which toured South Africa in 1974 under the esteemed Irish forward Willie John McBride, that went 22 games unbeaten and triumphed 3-0, with one drawn, in the test series. The test series was beset by violence. The management of the Lions concluded that the Springboks dominated their opponents with physical aggression. At that time, in test matches the referee was from the home nation, there were only substitutions if a doctor agreed that a player was physically unable to continue and there were no video cameras and sideline officials to keep actions such as punching, kicking, and head-butting to a minimum. The Lions decided "to get their retaliation in first" with the infamous '99 call' (99 is a shortening of 999 which in Britain and Ireland is the phone number for the emergency services such as the police, ambulance or fire brigade). The idea was that a South African referee would be unlikely to send off all of the Lions if they all retaliated against "blatant thuggery". At the battle of Boet Erasmus Stadium, one of the most violent in rugby history, there is famous video footage of JPR Williams running over half of the pitch and launching himself at van Heerden after such a call.
J.B.G. Thomas (1974) The greatest Lions (Pelham Books)Jenkins, Vivian (1975). Rothmans Rugby Yearbook 1975-76. Brickfield Publications Limited.