Lupin III aims to steal a Japanese cultural treasure "Jigoku Nyorai Zo," which is found in the recreation facilities of Nazi Germany. However, this valuable object is also targeted by Morgana, a mysterious figure who leads a ninja thief gang.

Two jewels are the key to the ancient treasure of Yaobikuni. But legend has it that the only person who can find the treasure is one who can walk the path of death.

And why is Lupin interested? This is the one treasure his grandfather sought but did not steal.

(Source: AniDB)

Lupin has become a suspect in the murder of a professor named Theo Argent. The professor had just discovered the missing page of Marco Polo's Record of Observations of the East travel journal. As Lupin is being pursued by the police, he ends up getting unlikely help from the granddaughter of Theo Argent, Lisa. 

(Source: ANN)

The story is set in Shahalta, a tiny European city-state floating in the air with practically no contact with the outside world for years. The government is transitioning from a monarchy to a republic, and to celebrate the occasion, a national treasure exhibition is being held. Lupin infiltrates the exhibition for the secret royal treasures, but not before sky pirates snatch them first.

(Source: ANN)