Please answer the following question: Build a movie plot around this: What do they try to seal from the German marshaling yards at Mostar? Explosives
A:
In 1943, after their successful mission on the Greek island of Navarone, Major Keith Mallory (Robert Shaw) and Sergeant John Miller (Edward Fox) are sent to find and kill Nicolai. Originally thought to be a traitor who informed the Germans about Miller and Mallory during the Navarone mission, Nicolai is now known to be Colonel von Ingorslebon, a dedicated German spy believed to have infiltrated the Yugoslav Partisans as "Captain Lescovar" (Franco Nero).To get to Yugoslavia, the two men pair with "Force 10", an American sabotage unit, led by Colonel Mike Barnsby (Harrison Ford), which has its own mission there. To maximise security, Force 10 steals a Lancaster bomber from a British air base in Termoli, Italy, rather than requisitioning one; but they are spotted by Military Police MPs before they can take off. Weaver (Carl Weathers), a US Army sergeant under arrest by the MPs, joins with Force 10 and forces his way onto the plane. Barnsby and crew successfully "escape" Termoli, only to be shot down by Luftwaffe night fighters. Only Barnsby, Mallory, Miller, Weaver, and Force 10 member Doug Reynolds (Angus MacInnes) manage to escape the crippled plane.On the ground, the survivors run across a group they believe to be their allies, Communist Yugoslav Partisans, led by Captain Drazak (Richard Kiel). Force 10's rescuers are soon revealed to be collaborationist Chetniks (nationalist Serb guerrillas) under German control. The Germans take the team into custody but do not know their mission, so Mallory and Barnsby tell the commander, Major Schroeder (Michael Byrne), that they are criminals fleeing Allied authorities. To keep Schroeder from opening Miller's suitcase, which contains his special explosives, Mallory tells him that it contains a new wonder drug called "penicillin" which will spoil if exposed to air. By the next morning, the prisoners are told that Schroeder has opened the case, finding it full of firewood. Surprised, Mallory and Barnsby improvise an excuse, "admitting" they buried the samples. Schroeder...