Duckula decides that Nanny needs psychiatric help, so he transports the caste to Austria. Unfortunatly, the castle ends up in Australia instead. There, Duckula accidentaly gives away the castle's coo-coo clock, whick is a part of the mechanism that allows the castle to transport. He, Igor, and Nanny travel all over Australia to get it back.
While visiting the Milan Opera House, Duckula, Nanny, and Igor run into the mysterious phantom. The phantom's servant turns out to be an old school chum of Igor. The action picks up as the Phantom kidnaps Nanny. In trying to rescue her, the opera house is destroyed and the Phantom goes to America to haunt the Grand Ole Opray.
French thieves Gaston and Pierre plan to break into Castle Duckula to steal a priceless vase. They are caught, and inform Duckula that the vase is actually part of a map that leads to the treasure of Mandarin leader How Fat. Duckula goes in search of it and ends up on the island of Moi Chow in a race against How Fat and the mutinous penguins to the treasure.
Duckula travels to England to hear the will of the Duke of Mallardborough. When it is revealed that the Duke was murdered, many different suspects are interrogated. The investigation begins to focus on Duckula, who is coerced into confessing. He is put on trial and, just before the verdict is announced, the Duke appears, alive, and states that his death was a hoax.
Duckula, sick of the old castle, transports it to California so that he can sell it and make a big profit. He has trouble finding a buyer, though, since Igor, not wanting to leave the castle, shows all the buyers the torture rooms. Meanwhile, Von Goosewing has followed them in a continued effort to kill Duckula.
The Count transports the castle to Manhattan, where Transylvanian style suddenly becomes the newest fasion fad. Seeing his chance to make a fortune, Duckula sells off most of the contents of the caslte, including Igor. Duckula and Nanny use the money to have a grand time in the city. Unfortunately they may be stuck there, since one of the things they sold was the clock that controls the transport mechanism.