'In 1921 during the Irish War of Independence, the IRA ambush a police convoy carrying two captured members of the IRA, Commandant Connolly and Hogan of headquarters staff. After freeing the two men, the IRA becomes suspicious of one of their members, James Hennessey, whom they believe is an informer. The police raid the pub where the IRA men are drinking. English intelligence officer Captain Wiltshire later arrests Hennessey as a means of getting information from him. County Inspector John Hannay of the RIC, with whom Wiltshire works, is concerned that his fiancee, Maureen Elliot, may be in danger. He sends Wiltshire with a coded message to pass on if she needs help, but Maureen realises that her brother, Terence, is a member of the IRA. Maureen overhears that Ballyfinlan Castle, an IRA hideout, is due to be raided by the RIC and British Army. On her way there to warn her brother she is intercepted by the police for breaking the curfew. When she is brought to the barracks, Hannay becomes suspicious of her story that her car broke down. At Hennessey's trial by the IRA at Ballyfinlan Castle, their secret leader, known as Nick O'Dea, who in reality is Terence Elliot, uncovers that evidence against Hennessey. During the raid by the police on the hideout, Hennessey is shot by the IRA but most of the IRA men are captured. While Connolly and Hogan escape, Terence is killed by Wiltshire. Connolly and Hogan plan revenge on Wiltshire for Terence's death and they force Maureen to set him up. She rings the barracks and asks Wiltshire to come to her. She rings the barracks again and leaves the coded message which alerts Hannay to the presence of the IRA. Wiltshire arrives at the Elliots' house and is tied up. In an attempt to thwart his execution, Maureen sabotages the getaway car, but they discover the ruse and escape. Hannay arrives, and seeing Maureen's anxiety, realises that she is in love with Wiltshire. After catching up on the getaway car, Hannay and his men force Connolly and Hogan to flee and to leave Wiltshire behind. Later, Hannay tells Maureen and Wiltshire that it was he who killed her brother, recognising that it is Wiltshire whom Maureen really loves.' Source - Kevin Rockett, The Irish Filmography, Dublin, Red Mountain Press, 1996.