Rich, handsome, young and unmarried, Rowland Mallet sets off for Europe amid high expectation of enjoying the freedom that comes with privilege. At stop by dear cousin Cecilia starts unpromisingly with a judgmental lecture on living a life without purpose and lacking any ambition. To this charge he responds by saying he will begin collecting art to be donated to museums. To this promise, Cecilia responds by introducing him to the work of her Roderick Hudson. Mallet is impressed by the statuette and the next day arranged to meet Roderick. Hudson hails from Virginia and currently employed as a law clerk. Something about the artistic soul being trapped in the judicial system appeals to Mallet and he is moved to extend an offer to join him in Rome where he can more properly pursue his obvious gifts and talent for sculpture. Roderick agrees, much to the displeasure of both his overbearing mother and Cecilia. Mallet does his best to soothe any trepidation caused by suspicion of his own intentions. Meanwhile Mallet has become charmed by Roderick’s distant cousin Mary Garland who also raises doubts about his lack of work. Only as the time draws to finally set sail for Europe does Mallet learn that Mary is already engaged to Roderick.
Three months have passed and the yoke of grunt work has fallen from the shoulders of Roderick. He is making money and just as quickly spending it. His fame as a sculptor is growing throughout Rome’s social circles when he completes unveils new statues of Adam and Eve. In the wake of Roderick’s revelation, Mallet has been struggling to get past his attraction to his friend’s fiancé , primarily by redirecting his attention to an attractive and wealth ex-patriate painter named Augusta. While at a social function, Roderick haughtily announces his ambition to join the great sculptors whose work define the Italian art. Warnings about failing to live up to premature promise and the effects of Bohemian life on ambition fail to contain his pride which suffers a fall when inspiration suddenly fails to strike. Roderick attempts to escape through lonely self-exile in Switzerland and Germany while Mallet heads to England. While there, he receives word from his friend about extensive gambling debts and agrees to bail his the sculptor from his debt. Upon returning to Rome Roderick is force to admit that he has run out of ideas. In the interim, yet another American artist in Rome, Sam Singleton, has become the new toast of the town. And then the men are visited by the eccentric Mrs. Light and her daughter Christina who is as beautiful as her mother is unpredictable. So taken is Roderick by the charms of Christina that offers to transform her beauty into stone.
While falling in love with Christina, Roderick extends an invitation to Mary and her mother to visit. When his bust of Christina is unveiled, it is an immediate sensation. Augusta arranges for Roderick to meet a rich American with money to burn on art commissions named Mr. Leavenworth. The real reason for Mr. Light’s arrival is revealed by Christina who complains that her efforts to find a husband are nothing less than immoral. When she asks Mallet about Roderick’s personal life, Christina learns of the engagement to Mary which angers Roderick and stimulates accusations of Mallet attempting to exert too much control over him. The argument intensifies and leaves Roderick once again feeling that inspiration has betrayed him. Sinking deeper into depression, his outlook becomes more cynical and increases his susceptibility to giving in to this Bohemian desires. Mallet is compelled request that Christina stay out of Roderick’s life unless her intention is marry him. Day later she claims she has done as he asked.
Mr. Leavenworth announces Christina has become engaged to the Prince which causes Roderick to angrily refuse to complete his commission. After another argument, Mallet leaves his friend behind to deal with his Christina obsession while he spends his days in Florence in much the same emotional turmoil over Mary. Experiencing almost a religious epiphany, Mallet heads back to Rome after asking Roderick to meet with his mother and Mary. Roderick agrees but fails to show at their arrival. In the intervening years, Mary has managed to mature in every way that Roderick has not. The tension is brittle and uncomfortable, but Roderick is the catalyst for it all. When they meet Christina the next day, Roderick hints that she may not become a Princes, after all. Roderick spends the mornings working on a bust of his mother, which frees up Mallet to take Mary on tours of Rome where her newfound maturity is also expressed in a serious understanding of the cultural significance of the sights they see. The sculpture of Mrs. Hudson completed, Mallet begs his friend to leave Rome and do everything he can to fix things with Mary. Roderick is insistent upon staying in order to attend Christina’s wedding to the Prince. And then arrive a social gala at which Christina and Mary finally meet.
Mary is instantly suspicious of Christina’s motives regarding Roderick which intensifies after she suddenly breaks her engagement to the Prince. Fueling the mistrust is Roderick’s decision to banish them for a week as he indulges in the news the wedding has been called off. When Mallet arrives to see Sam Singleton off in his voyage back to the America, he learns that Christina and the Prince have just been married that very morning. Roderick confesses his desire for Christina to his mother and also admits that he is bankrupt. Mallet makes arrangements for them to take up residence at a villa in Florence. The villa turns out to be a place of great unhappiness for everyone as Roderick falls deeper in one of morose moods of depression and self-pity. At the suggestion that he can be just as much a failure back home, Mallet moves to persuade him to give Europe another year, but the decision has been made to leave Italy and set out for Switzerland. Feeling both guilt and excited at the prospect, Mallet begins to ponder if Roderick’s rejection of Mary will make her available to him. A dip of into the shallow end of the pool of romantic overtures proves the water far too cold to wade in any deeper.
Roderick’s depression over Christina is turning into bitter outrage at what he views as her betrayal. Sam Singleton arrives back in Europe and quickly proves himself an art factory. Mallet runs into the Prince and Christina who confesses that current circumstances are not an indication of her feelings toward Roderick, but are instead the result of being forced to do something against her will. To prove her lack of deep feelings for the Prince, she also announces her intentions to enjoy a life on the edge. That edginess is quickly revealed when Roderick comes to Mallet asking for enough money to meet with Christina furtively. Mallet is hesitant about this loan so Roderick seeks assistance from his mother and Mary who both insist they haven’t the funds. An argument between the two men erupts over open behavior and secret motivations until Mallet finally blurts out how he has felt about Mary all along. Roderick disappears alone into the mountains shortly before a threatening storm approaches. When he fails to return by the next day, Mallet and Sam Singleton set off on a searching expedition that ends with the discovery of the lifeless body of Roderick Hudson far below the cliff from which he feel. Mallet, Mary and Roderick’s mother soon return home to America.