Matthew Bannister on

Lee Evans, the world-record-breaking American sprinter who took part in black power protests at the 1968 Mexico Olympics.

Yuan Longping, the plant scientist who developed hybrid varieties of rice that increased yields dramatically and so saved millions from hunger.

Bill McCall, the General Secretary of the Institution of Professional Civil Servants who challenged Margaret Thatcher over union recognition at GCHQ.

Alix Dobkin, the folk singer and lesbian activist who performed to women-only audiences.

Producer: Neil George

Interviewed guest: Tommie Smith

Interviewed guest: Professor Douglas Hartmann

Interviewed guest: Keith Bradsher

Interviewed guest: Charles Harvey

Interviewed guest: Liza Cowan

Archive clips used: Athletics_400 Metres Final: BBC One, TX 18.10.1968; A Classless Civil Service: Radio 3, TX 10.7.1968; BBC News: BBC One, TX 28.2.1984