When he first appears in the novel in Chapter Four "The First Customer," Holgrave converses with Hepzibah about the opening of her cent-shop. He attempts to encourage her in her endeavors and expresses his critical views of aristocracy and gentility.
In the chapter "The Pyncheon Garden" Phoebe meets Holgrave. They have a humorous conversation about the Pyncheon chickens, revealing the lighter side of Holgrave's character. He tells her about his efforts in gardening and his work as a daguerreotypist. He claims that a daguerreotype can reveal an individual's secret character in the way a painter never dares.
In the first portion of Chapter 12, "The Daguerreotypist," Hawthorne offers more insight into Holgrave's character, his views of social conditions, and his preference for the future over the past. Holgrave admits his humble origins and lack of formal education. His comments reveal his lack of a fixed and stable place in the social order, suggesting his alienation from middle-class life. His participation in a Fourierist community links him to utopian thinking of the nineteenth century. The narrative suggests, however, that beneath his surface changeability, Holgrave has "never violated the innermost man."
Later in Chapter 12, Holgrave admits his interest in the Pyncheons and their past, but does not explain a reason for it. He also remarks upon the difference between his sensibility and Phoebe's. The narrative suggests that Holgrave's idealism is appropriate for a man of his age (22), but leaves the possibility of his acting on his professed beliefs more open-ended.
Toward the end of Chapter 12, Hawthorne presents the continuing interaction between Holgrave and Phoebe, during which Holgrave declares his rejection of the past and admits that he writes stories for magazines.
In Chapter 13, Holgrave narrates his story of "Alice Pyncheon," whom he depicts as a proud young woman who is mesmerized and ultimately destroyed by one of the Maules.
At the beginning of Chapter 14, "Phoebe's Good-by," Holgrave discovers that he has mesmerized Phoebe with his words and has her under his power, but the decision he makes reveals that he will not exploit her as his ancestor had Alice.
During Phoebe's absence from the Seven Gables, Jaffrey invades the house, threatening Hepzibah. When Hepzibah discovers Jaffrey dead in the great chair, she and Clifford flee the house, leaving it eerily silent. Holgrave questions Uncle Venner about this silence at the beginning of Chapter 19, "Alice's Poesies," neither man having any idea what has happened. They comment on the possibility of ghosts and Venner hints at his awareness of Holgrave's love for Phoebe when he mentions Alice's poesies.
In Chapter 20, "The Flower of Eden," Phoebe returns to Seven Gables, and she and Holgrave realize that they are alone in the house. Holgrave tells her of Jaffrey's death and of the disappearance of Hepzibah and Clifford. He also informs her of his suspicion that it was Jaffrey who arranged the circumstantial evidence used to convict Clifford.
While he and Phoebe are alone, Holgrave professes his love for her and she admits her feelings for him. Holgrave also forecasts his own reversion to a more conservative sensibility, his acceptance of social norms and conventions that he had previously rejected.
Holgrave confesses that he is a Maule, reclaiming the part of his identity that he has kept hidden. His need to conceal his true self has served as one sign of his alienation in the novel, but his relationship with Phoebe has allowed him to resolve this issue.
In the final chapter, "The Departure" Holgrave admits his new conservative leanings, a change of sensibility that surprises Phoebe and has prompted comment from many critics. Holgrave makes no further mention of an artistic or authorial vocation, suggesting that his newfound love and contentment have eased the alienation that aided his artistic pursuits.

Full text of The House of the Seven Gables

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