Plot
During a school trip to the beach, Maurice Hall, an 11-year-old schoolboy, receives instructions about the "sacred mystery" of sex from his teacher Mr. Ducie, who wants to explain to the fatherless boy the changes he will experience in puberty. Maurice is left feeling removed from the depiction of marriage with a woman.
Years later in 1909, Maurice is attending the University of Cambridge, where he strikes up a friendship with two fellow students: the aristocratic eccentric Viscount Risley and the rich and handsome Clive Durham. Clive falls in love with Maurice and surprises him by confessing his feelings. At first, Maurice reacts with horror, but he soon realises that he feels the same. The two friends begin a love affair but, at Clive's insistence, their relationship remains non-sexual. To go further, in Clive's opinion, would diminish them both. The upper-class Clive has a promising future in politics ahead of him and does not want to risk losing his social position. Their close relationship continues after Maurice leaves Cambridge and begins a new career as a stockbroker in London.
The two friends keep their feelings secret but are frightened when Risley is arrested and sentenced to six months' hard labour after soliciting sex from a soldier. Clive, afraid of being exposed as homosexual, breaks up with Maurice. After his return from a trip to Greece, Clive, under pressure from his widowed mother, makes overtures toward Maurice's sister until a furious Maurice intercedes. He tries to rekindle their relationship, but Clive spurns him decisively. Clive soon marries a naïve rich girl named Lady Anne Scott and settles into a life of domesticity at his estate, Pendersleigh.
Maurice seeks the help of his family physician, Dr. Barry, who gives him a physical examination and dismisses Maurice's doubts as "rubbish". Maurice then turns to Dr. Lasker-Jones, who tries to "cure" his homosexual longings with hypnosis. During his visits to Pendersleigh, Maurice attracts the attention of Alec Scudder, the under-gamekeeper who is due to emigrate to Argentina. Maurice not only fails to notice Alec's interest in him, but initially treats him with contempt. This does not discourage Alec, who watches Maurice's window at night. Simcox, the butler at Pendersleigh, suspecting the true nature of Maurice and Clive's past relationship, hints to Alec about Maurice's nature. One night, Alec climbs a ladder and enters Maurice's bedroom through an open window. He kisses Maurice, who is completely taken by surprise, but does not resist his sexual advances.
After their first night together, Maurice receives a letter from Alec proposing they meet at the Pendersleigh boathouse. Maurice wrongly believes that Alec is blackmailing him and returns to Lasker-Jones, who warns Maurice that England is a country that "has always been disinclined to accept human nature" and advises him to emigrate to a country where homosexuality is no longer criminal, like France or Italy. When Maurice fails to appear at the boathouse, Alec travels to London and visits him at his offices, causing some surprise amongst Maurice's colleagues.
Maurice and Alec go to the British Museum to talk, and the blackmail misunderstanding is resolved. Maurice begins to call Alec by his first name. They spend the night together in a hotel room, and as Alec leaves the next morning he explains that his departure for Argentina is imminent and they will not see each other again. Maurice goes to the port to give Alec a parting gift, only to discover that Alec has missed the sailing. Maurice goes to Pendersleigh and confesses to Clive his love for Alec. Clive, who was hoping Maurice would marry, is bewildered at Maurice's account. The two separate and Maurice goes to the boathouse looking for Alec, who is there waiting for him. Alec has left his family and abandoned his plans to emigrate to stay with Maurice, telling him, "Now we shan't never be parted".
At home with his wife, Clive's preparations for bed are interrupted by reminiscences about his time with Maurice.