Lupin the 3rd: Blood Seal of the Eternal Mermaid

An Aquamarine gemstone, the Mermaid's Scale, appears in a secret, underground auction. The queen of the underworld (nicknamed the "Bearslayer") coerces the professional jewel-lifter Lupin into stealing the rock for her. Lupin swipes the stone, and quickly discovers not only that it's a forgery, but that the real Mermaid's Scale is part of an unsolved riddle that leads to transcending mortality! So…