Larry Marley to come to fruition, he joined the blanket protest in the Maze's H-Blocks for four years. In September 1983, he helped Brendan McFarlane, Bobby Storey and Gerry Kelly to orchestrate the successful mass escape of 38 republican prisoners from the Maze. It was the largest prison escape in British penal history. According to a BBC documentary about the escape, Marley was the mastermind, having come up with the idea with the aim of embarrassing British Prime Minister Margaret Thatcher, as the Maze was considered to be one of the world's most secure prisons. Marley, unlike his three co-conspirators, did not
Mountjoy Prison helicopter escape thousand members of the Irish Defence Forces and Garda Síochána ensued. Mallon was recaptured at a Gaelic Athletic Association dance in a hotel near Portlaoise on 10 December 1973, and imprisoned in Portlaoise Prison. He escaped from there in a mass break-out on 18 August 1974, when nineteen prisoners escaped after overpowering guards and using gelignite to blast through the gates. He was recaptured in Foxrock in January 1975 and returned to Portlaoise Prison. O'Hagan was recaptured in Dublin in early 1975, and also imprisoned in Portlaoise Prison. After the end of his original twelve-month sentence, he was immediately arrested