The Cousins by Karen M. McManus Summary

The Cousins by Karen M. McManus follows three estranged cousins—Milly, Aubrey, and Jonah Story—who receive a mysterious invitation from their wealthy, reclusive grandmother to work at her island resort for the summer. Twenty-four years earlier, she disinherited their parents with a cryptic letter stating "you know what you did." As the cousins uncover dark family secrets, they discover nothing about their family is what it seems.

The Cousins is perfect for young adult mystery and thriller enthusiasts who enjoy layered family dramas with multiple plot twists. Fans of Karen M. McManus's previous works like One of Us Is Lying will appreciate her signature suspenseful storytelling. Readers who love stories featuring complex family dynamics, unreliable characters, and beach resort settings with dark undercurrents will find this book highly engaging and fast-paced.

The Cousins is worth reading for those seeking a well-paced YA thriller with compelling character development and shocking revelations. Most readers praise Karen M. McManus's ability to deliver unexpected twists and maintain tension throughout. While some find certain plot elements predictable, the majority appreciate the intricate family mystery, likable main characters, and the full-cast audiobook narration that enhances the reading experience significantly.

The Cousins by Karen M. McManus is a young adult mystery thriller with elements of family drama. The novel combines suspenseful investigation with coming-of-age themes as three teenage cousins unravel decades-old secrets. It features multiple POVs, flashback sequences to 1986, and classic mystery elements including hidden identities, suspicious deaths, and a central whodunit question about why the Story siblings were disinherited.

The central mystery in The Cousins revolves around why grandmother Mildred Story disinherited her three children twenty-four years ago with a letter saying "you know what you did." The cousins investigate connections between two suspicious deaths—Matt, the assistant's son who drowned, and Kayla, who died in a car accident. As they dig deeper, they uncover that their grandmother may not be who she claims to be.

The three Story cousins are Milly, the cool and sharp-witted daughter of Allison; Aubrey, the insecure but kind swimmer whose father is Adam; and Jonah, the mysterious and intelligent son of Anders who secretly sent an impostor in his place. Despite being related, they barely know each other due to their parents' estrangement. Throughout the summer, they bond over shared trauma and become a chosen family unit.

The Cousins ends with the revelation that "Mildred" is actually Theresa Ryan, the former assistant who orchestrated a decades-long fraud with lawyer Donald Camden to control the Story fortune and seek revenge for her son Matt's death. Theresa dies in a fire she ordered at Catmint House. The entire Story fortune is gone, squandered over twenty-four years. The cousins forge a genuine connection and choose to maintain their relationship, creating a new, healthier family legacy.

The Cousins features several shocking twists:

• Jonah Story is revealed to be an impostor named Jonah North sent by the real Jonah
• The grandmother they've been meeting is actually Theresa Ryan, not Mildred Story
• Uncle Archer has been working undercover on the island as bartender Chaz
• The entire Story fortune has been embezzled and destroyed

These revelations cascade during the dramatic Summer Gala confrontation.

The impostor reveal in The Cousins is twofold: First, Milly discovers that "Jonah" is actually Jonah North, paid by their real cousin to attend in his place while he goes to science camp. Second, and more dramatically, "grandmother Mildred" is revealed to be Theresa Ryan, the former assistant seeking revenge for her son's death and who has been running an elaborate fraud scheme for twenty-four years with accomplices.

The Story family fortune was systematically embezzled and squandered over twenty-four years by Theresa Ryan (posing as Mildred), Donald Camden, and their accomplices. The remaining assets and uninsured valuables were destroyed when Theresa ordered her sister Paula to set fire to Catmint House to eliminate evidence. This complete loss of wealth underscores Karen M. McManus's theme that material inheritance is fleeting compared to authentic human connections.

The Cousins includes light romance elements appropriate for young adult readers, featuring kisses between characters. Milly and the impostor Jonah develop romantic feelings and share a kiss at the Summer Gala, which becomes a dramatic plot point when their relationship is publicly exposed. The romance is secondary to the mystery and family drama, serving to complicate relationships and raise the stakes during critical revelations about identities and deception.

The Cousins showcases Karen M. McManus's signature style of layered mysteries and shocking twists found in One of Us Is Lying and Two Can Keep a Secret, but focuses more on family drama than school-based settings. While some readers find it slightly less gripping than her debut, others praise its complex plotting and character development. The full-cast audiobook production enhances the experience, and the multiple POVs with flashback structure demonstrates McManus's evolving narrative sophistication.