Barreto sticks close to the life of one of the kidnappers, Fernando Gabeira, which may explain why the scenes among the young revolutionaries feel so credible, and so claustrophobic. Particularly effective is actress Fernanda Torres as Comrade María, the most strident and ideological of the cadre. There's also a winning performance by American comic actor Alan Arkin as the Republican ambassador, who proves a model prisoner.

The real-life Gabeira suffered many years of forced exile, and menial jobs, for his part in the kidnapping. Today he's an active member of Brazil's Green Party and an avowed pacifist. Ambassador Elbrick has died in the interim, but his daughter stated at a Four Days press conference at last year's Berlin Film Festival: "My father felt close to those who abducted him. He was treated well. He was impressed by their idealism and felt an enduring connection."