Herman Munster (Fred Gwynne) and his wife, Lily (Yvonne De Carlo), learn from Cavanaugh Munster's will that they have inherited an English manor known as Munster Hall in Shroudshire, England, and that Herman has inherited the designation Lord of the Manor as "Lord Munster". The family boards the famous American transatlantic passenger ocean liner SS "United States" to England. Herman gets seasick, Marilyn (Debbie Watson, replacing TV series player Pat Priest in a controversial move) encounters a new love and suitor Roger Moresby (Robert Pine). Grandpa (Al Lewis) gets turned into a grey wolf upon accidentally consuming a wolf pill and has to be sneaked through British immigration and customs.