Devlin became a street activist in the late 1960s and was heavily involved in the Battle of the Bogside in 1969. She represented the local residents at a moment in history which is widely acknowledged as the beginning of Northern Ireland's 30 year ‘troubles’. She subsequently, at the age of only 21, became the youngest women ever to be elected to the House of Commons, Westminster; with her campaign slogan "I will take my seat and fight for your rights" Devlin signalled her rejection of the traditional Irish Republican tactic of abstentionism.

Bernadette is composed entirley of found footage which is presented without commentary or context. It links the state of being lost among representations of the past to one of obsessive, even sexual, enthrallment. The film opens with black and white footage of Bernadette's bare skin: her toes, her feet, her arms, her eyes. This extolling of the parts of the body is a cinematic version of the blason, an adoration of 'the beloved' which has migrated from its origins in French poetry to film (Jean Luc Godard's Le Mépris also opens with a scene of this sort, dedicated to Brigitte Bardot). This portrayal of the beloved is subsequently overturned and then almost forgotten in the rest of the film, which shows a firebrand of a woman, one who, after being prohibited from speaking in Parliament after Bloody Sunday, punched the Home Secretary (and later said her only regret was that she "didn't get him by the throat").