乡绅沃辛（Michael Redgrave 饰）来到伦敦城内拜访阿尔及（Michael Denison 饰），而实际目的是后者的表妹格温多兰，为了便于探望格温多兰，沃辛虚构了一位伦敦的不肖昆仲欧内斯特。阿尔及对沃辛在乡下监护的姑娘西西莉情有独钟，于是出面帮助沃辛向格温多兰求婚，尽管欧内斯特（真诚）这个假名对姑娘有莫名的吸引力，但沃辛的弃儿出身让未来岳母一口回绝。阿尔及在沃辛之前赶到他乡下的住处，装作欧内斯特如愿结识了西西莉，未几沃辛与格温多兰母女先后抵达，虚拟人物“欧内斯特先生”的骗局终被揭穿，两位男士一时手足无措，但突然浮出水面的一段陈年往事，让两对恋人的前途峰回路转。　　本片根据王尔德同名作品改编。

Jim Ackland, who suffers from a head injury sustained in a bus crash, is the chief suspect in a murder hunt, when a girl that he has just met is found dead on the local common, and he has no alibi for the time she was killed.

Father Brown tries to transport a historically important cross to Rome engaging in battles of wits and faith with a thief and pursuing policeman. The thief, named Flambeau (Finch), is a master of disguise and is elusive, as Father Brown pursues him and tries to convince him to abandon his criminal career.　　During the making of the film, Alec Guinness was mistaken by a small boy for an actual priest. This episode appears to have played a part in Guinness's later conversion to Roman Catholicism.