Lupin the Third: Blood Seal of the Eternal Mermaid(2011)

Gemstone, the Mermaid's Scale, appears in a secret, underground auction. The queen of the underworld coerces Lupin into stealing the rock for her. Quickly discovering not only that the stone is a forgery, but that the real Mermaid's Scale is part of an unsolved riddle that leads to transcending mortality!