"In a peaceful retirement village, four unlikely friends meet weekly in the Jigsaw Room to discuss unsolved crimes; together they call themselves The Thursday Murder Club. There's Red Ron, the infamous former socialist firebrand, still causing trouble; gentle Joyce, widowed, pining for another resident, but surely not as innocent as she seems; Ibrahim, a former therapist who understands the darker side of human nature; and Elizabeth? Well, no one...

Arthur sets out to save his family's home from real estate developers when his grandfather mysteriously disappears. When he finds his grandfather's ancient clues of treasure, he unlocks a passageway that leads to a spectacular world with little people.