In Stephen King's "Under the Dome," the quote "Two can keep a secret if one of them is dead" highlights the fragility of trust and the consequences of secrets. It suggests that keeping a secret is often impossible when multiple people are involved, and the only way to ensure confidentiality might involve extreme measures. This idea reflects the deeper themes of secrecy and betrayal within the narrative, where characters face moral dilemmas and the resulting chaos from hidden truths.

This quote illustrates the tension that arises in the novel as the characters grapple with their own secrets and the impact these have on their relationships and community. As the dome traps them, the isolation intensifies the pressure to either reveal or protect these secrets, leading to tragic outcomes. Ultimately, King's work examines how secrets can destroy lives when unchecked, showcasing the dark side of human nature and the lengths individuals will go to in order to protect themselves.