In "Pony Island Part 2: The Bonds of Friendship," former President Albert Solanges of Saint Katherine receives an unexpected invitation from his old friend and successor, Dr. Lucien Lavel, now the island's absolute ruler. After a military coup that forced Albert into exile, Lavel extends a blanket amnesty, restores their property, and personally urges the family to return home. Albert, trusting Lavel's word despite past betrayals, agrees along with his wife Helen and her niece Marianne, who is eager to visit her mother's birthplace for the first time. Meanwhile, on the island, Lavel prepares a significant celebration for his son Robert's 21st birthday, marking his coming of age as the legal heir, while reflecting on the shifting dynamics of power and loyalty.

Upon arrival at the newly built Lavel International Airport, the Solanges family is shocked by their immediate arrest on charges of treason and espionage. Albert is separated and held, while Helen and the bewildered Marianne are taken to secret police headquarters for intense interrogations. The women endure harsh procedures and isolation in cold basement rooms, their pleas for explanation falling on deaf ears as they are confined in restrictive holds. Lavel's chief of security, Jean-Paul St. Juste, assures the president that any potential unrest from protesters or U.S. intervention will be swiftly managed, given the regime's strengthened alliances under recent political changes in Washington.

As tensions escalate, Lavel confronts Albert in the presidential palace, revealing the depth of his transformed ambitions and the harsh reality of unchecked authority. The women are relocated to an underground prison, subjected to relentless psychological pressure designed to break their resolve. One week later, during a twisted anniversary celebration for Albert and Helen, the captives witness further manipulations, including coerced displays of submission and public humiliations under the guise of hospitality. The story culminates in grueling endurance tests for the imprisoned women, including the Jackson sisters from Part 1, as Lavel and his son revel in their control, underscoring themes of shattered trust, the corrupting nature of power, and the fragility of personal bonds in the face of tyranny.