Hitler's plan to loot a treasure-laden Greek island is under way. A prison camp is built where the inmates gig up priceless art under the eye of the Austrian commandant Major Otto Hecht (Roger Moore). Zeno (Telly Savalas) the island's resistance leader and Eleana (Claudia Cardinale) scheme to defeat the occupiers. Leading a group of freedom fighters. They clash with the Nazis as they try the lives of condemned prisoners and the treasure hidden in the mountaintop monastery.