In La Pasionaria, a historical novel based on true events, a young unemployed Welsh coal miner embarks on a tortuous walk on the Jarrow Hunger March that takes him from the north of England to London and finally, to a confrontation with the British government. Dai Powell journeys across the English Channel through France to Spain where the Communists are inspired by La Pasionaria, a crusading woman who passionately believes that Communism will eventually overtake the world. As La Pasionaria becomes the icon of the Republicana and the unemployed workers of Spain, Powell volunteers to fight for the Republican Government against Generalismo Francisco Franco's Nationalist aggressors. Powell falls in love with a Spanish military nurse, but also witnesses the horrific atrocities committed under Franco's order. Powell can only watch as brutal Nationalist soldiers tear babies away from their mothers and, after placing their parents in front of firing squads, send the children to orphanages where they are brainwashed into believing the ruthless politics of fascism.
After Powell is expatriated from Spain with the rest of his comrades, Powell must make a dangerous undercover return in an effort to rescue his lover and their child from the barbarous Nationalists.