摩斯探长第四季英文片名:《mositanchangdisiji》,发布于1990年,由约翰·马登执导,并且由编剧携幕后团队创作。集众多位约翰·肖,凯文·沃特利,杰弗里·帕尔默,大卫·尼尔,芭芭拉·雷吉-亨特,皮尔斯·奎格利,迈克尔·阿特威尔,谢丽尔·坎贝尔,John,Joyce,伊恩·布林布尔,汤姆·威尔金森,Irene,Richard,乔治·科斯蒂安,Denys,Hawthorne,Sydnee,Blake,柯林·德克斯特等著名实力派明星加盟。并于1990年在英国上映。
Morse finds himself the subject of a murder investigation when his friend, Beryl Newsome, is murdered at a rehearsal of the Magic Flute and he foolishly touches the murder weapon. Morse is suspended and DCI Bottomley, with DS Lewis assisting him, is put in charge of the case. Morse feels that he was set-up and looks to his past to see who, among the many criminals he arrested, might now be setting about seeking revenge. When someone scratches masonic symbols all over his car and he is reported for erratic driving, Morse wonders if Masons may somehow be involved. When a large number of his personal items are found in Beryl's apartment, Morse is placed under arrest.