the nature of the target, only that it was a highly rated objective in Norway that could not be reached by the RAF until the Mosquito became operational. There was such a target, the molybdenum mine in Knaben, southern Norway. Typical of the mineral wealth that Hitler stated was worth the sacrifice of a significant portion of the Kriegsmarine, Knaben could produce four-fifths of Germany's requirements for molybdenum, an important element in the production of armour plate. The mine at Knaben was too small to hit in a night raid, and sending heavy, long-range bombers in daylight would have met with disaster. Light bombers such as the Blenheim were ideal for the job, but did not have the necessary range. However, Knaben was within the range of the Mosquito, and 139 Squadron was given the task on 3 March 1943. Nine Mosquitoes were dispatched. All placed their bombs on target, though one failed to return. The target was out of action for some time and was later visited by the United States Army Air Forcess Eighth Air Force. The "jeep" partly hidden behind a bush in one of the Scottish Highlands training sequences is a post-war Land Rover, and the "German halftrack" is an Alvis Saracen. Land Rovers are seen in backgrounds of other scenes, such as when Grant is being driven from the airfield to be given the squadron's new assignment. The towing tractor seen on the airfield in the early part of the film is a Fordson E1A Major first produced in 1952. Reception 633 Squadron had its world premiere on 4 June 1964 at the Leicester Square Theatre in the West End of London. While critics derided the wooden acting and hackneyed plot, especially the miscast Mirisch Pictures contract star George Chakiris, the aerial scenes were considered spectacular and with Ron Goodwin's music remained the main attraction. Walter Mirisch recalled that the film earned nearly its entire cost of US$1.3 million out of Eady Levy receipts in the UK, making the film practically cost free when Mirisch released the film throughout the world. The great success of the film worldwide led to Mirisch making a series of UK based Oakmont Productions World War II productions shot mostly in the UK. It was among the ten most popular films of the year at the British box office in 1964. The film was re-released several times throughout the 1960s,