Although dramatised, the plot is closely based on the events of the revolution and many of the key characters are real - such as Captain Salgueiro Maia and Prime Minister Marcelo Caetano.

[2] The film opens on the evening of 24 April 1974, as a young conscript soldier (Daniel) kisses farewell to his girlfriend (Rosa) before boarding a train from Lisbon back to his Army base at Santarém.

Captain Salgueiro Maia arrests the base commander at gunpoint and orders the soldiers to assemble on parade in the middle of the night; he asks them to come with him to Lisbon to overthrow the government.

Rosa having arrived to babysit, Antónia then goes to a formal reception where she pleads with her brother Filipe Correia, a minister in the government, to release one of her students who had been arrested by the DGS (secret police).

Manuel and his colleagues prepare to seize control of the Rádio Clube Português, a radio station, from which communiques on behalf of the Armed Forces Movement will be broadcast.

There are several asides, including where the young conscript soldier in the opening scenes of the film meets Rosa again, placing a carnation in the barrel of his rifle (and are later discovered inside a military armoured car whilst making love).

The film closes with the release of the political prisoners, including Antónia's lover (Emílio), and Manuel and Maia narrowly avoid being attacked by a crowd when they are mistaken for DGS/PIDE officers rather than soldiers.