吉姆是一家小公司的老板,与同为公司一员的戴斯比相亲相爱。然而,当一夜他在梦中来到真实的一战时期,并搭求了一个迫降的飞行员比格斯之后,命运开始与他开起了种种不可思议的玩笑。在神秘出现的老头雷蒙德的解释下,吉姆相信自己与比格斯是跨越时空的兄弟,而自己也必须随时做好准备,与比格斯及其战友破坏掉德军秘密研制的声波武器。面对吉姆的种种怪异表现,戴斯经来到伦敦,并在一次意中被其带入那个战火纷飞的时代。One minute the New Yorker advertising expert Jim Ferguson is at a business party -- the next he finds himself way back in 1917 in a plane fight during World War I. Mr. Raymond explains to him that he has a time-twin, to whom he's relocated in space and time whenever one of them is in trouble. So he has to help his twin, biplane pilot Biggles, in his attempt to destroy a German super weapon, that could win their war. Of course it's hard for Jim to explain his sudden disappearances to his fiance, Debbie.