context: The Mouse that RoaredThe world's smallest nation, the Duchy of Grand Fenwick, which lies on the Swiss-French border, is quietly and prosperously ruled by the Grand Duchess Gloriana XII (Peter Sellers), with the assistance of the Hereditary Prime Minister, Count Rupert of Mountjoy (Peter Sellers), the Hereditary Field Marshall and Grand Constable, Tully Bascombe (Peter Sellers) and the Leader of the Loyal Opposition, David Bentner (Leo McKern).Disaster strikes, however, when the Duchy's only export, its wine, Pinot Grand Fenwick, is undercut in the United States by a Californian copy, Pinot Grand Enwick. Faced with bankruptcy, and having had no reply to its protests, the Duchy decides to declare war on the United States, Mountjoy having reasoned that it will certainly lose and will then be magnificently rehabilitated by the generous, victorious Americans. A Declaration of War is duly sent, but is considered a press-room joke by its recipient in Washington.Tully Bascombe, his lieutenant Will Buckley (William Hartnell), and twenty soldiers, in chain mail and armed with longbows, including Roger (Timothy Bateson) and Cobbley (Monte Landis) and (Alan Gifford), are sent to invade the United States, making the first part of their journey by bus and then by tramp steamer, captained by Pedro (Harold Kasket), encountering, en route, the QEII (captain Stuart Saunders, second officer Ken Stanley), which they mistakenly attack.In New York, an air-raid exercise has closed the entire city, with the exception of the laboratory of Professor Alfred Kokintz (David Kossoff) at the New York Institute of Physics, where he and his daughter Helen (Jean Seberg) are working on the new Q-bomb: an air-raid warden (Wally Brown) tries to get them to take shelter, but the Professor shows him the Q-bomb - an active working model on a hair-trigger - which he must deactivate first. The Grand Fenwick party land, but can find no-one to surrender to: in Central Park, they encounter a decontamination squad, Mulligan (Richard Gatehouse) and O'Hara (George Margo), who believe the Fenwickians in their shiny mail are "men from Mars" invading the city: this rumour rapidly spreads through the crowds in the shelters. The Grand Fenwick party takes the decontamination squad's van, trying to reach the Arsenal, but instead end up at the Institute of Physics, where they take Prof. Kokintz, Helen and the Q-bomb captive.General Snippet (Macdonald Parke), in charge of the New York exercise, alerted by an army captain (Bill Edwards) of the spread of rumours of "men from Mars", arrives with four New York policemen (Bill Nagy): they are also taken captive. Leaving the Grand Fenwick flag flying from the New York customs shed, the Grand Fenwick party re-embarks and returns home. Prof. Kokintz persuades Helen to try and seduce Tully, to persuade him to allow her father to deactivate the Q-bomb, but Tully, seasick, is unreceptive. In France, the Americans cannot get anyone (ticket collector, Jacques Cey) to listen to them.Back in Grand Fenwick the whole country is excitedly preparing to welcome the American victors, and planning what to spend the money on: they are dumbfounded when Tully arrives with his prisoners and declares that Grand Fenwick won. The Q-bomb is taken to the dungeons, Prof. Kokintz and his daughter to the castle, and the General and policemen to the "Museum of Ancient Torture" before the policemen are also taken to comfortable quarters in the castle: the General, insisting on his exact rights under the Geneva Convention, is shown to a small, dim cell with a tin plate of food.The U.S. Secretary of Defense (Austin Wills) finally puts together the pieces and realizes that the United States has been defeated: he has to tell the President, persuade the Pentagon generals (Lionel Murton) that this is the only course, and then go to Grand Fenwick to surrender. Meanwhile Grand Fenwick by its possession of the Q-bomb has now become the most powerful nation on the planet, as explained by the BBC Announcer (Colin Gordon).In Grand Fenwick's parliament, messages of support arrive from numerous other countries - all offering also to take the Q-bomb. The British (Charles Clay), French (Henry de Bray) and Soviet (Guy Deghy) Ambassadors convene at the frontier, and Will Buckley makes the U.S. Secretary of Defense, arriving to discuss the U.S.'s surrender, wait also. In frustration, Mountjoy and Bentner, and their parties, all resign, leaving Tully as the new Prime Minister.Mountjoy and Bentner now decide the only course is to help the Americans to escape and take the Q-bomb with them: they release the General and policemen, and give them the Q-bomb, and they also persuade Helen to leave, but not before Tully has declared his love for her: Prof. Kokintz, being entertained by the Duchess on the harpsichord, cannot be found. Taking the Duchess' elderly car, the Americans drive away, but are pursued by Tully. The car stalls and has to be pushed over a hill-crest: it then runs away with the General and the Q-bomb on board, running into a haystack, which sets the Q-bomb into high alert mode: tossed from hand to hand, it is captured by Tully and returned to the Duchy.Tully and the U.S. Secretary of Defense now discuss the peace treaty terms; the Californian wine will be discontinued, Prof. Kokintz and Helen, who will now marry Tully, will remain in Grand Fenwick, and so will the Q-bomb: as the Duchess points out, any atomic war would destroy Grand Fenwick anyway, and the big nations have not succeeded in nuclear disarmament, so now it is time for a League of Little Nations to try.Prof. Kokintz, finally allowed to disarm the Q-bomb, drops it! It was a dud all along: or was it? The little white mouse that emerges from it may know.
question: What was captured unitentionally by the Duchy's invading "army"?
answer: The Q-Bomb