After a diamond heist in Brazil, Lupin hides the gem in a doll and boards a plane headed out of the country. While on board, the doll is stolen by a little girl named Julia, whose nanny is none other than Fujiko Mine. Before Lupin can get the doll back, the plane is hijacked and the girl is kidnapped. The kidnappers are after the same thing that Fujiko is after - a book of Nostradamus prophecies hidden in Julia's father's tower. Lupin and the gang join forces to save the girl, get the diamond back, and discover the secrets surrounding the strange book. 

(Source: ANN)

Lupin, Goemon, and Jigen take a mini-helicopter and head to the mysterious “Drifting Island” looking for a treasure rumored to be hidden somewhere on it. Through their exploration of the island, the trio encounters the lethal “Nanomachine,” the island’s security system. The trio triggers the alarm, springing “the Nanomachine” to life. The key to solving the island’s mystery lies in the small nation of Zufu. This once prosperous nation is now ruled by the ruthless, knife-collecting, General Headhunter. Fujiko does her usual probing and hacks into General Headhunter’s computer hoping to find some crucial information. Zenigata has received a video message from Lupin in which Lupin announces his desire for the priceless treasure. Oleander, a fiery blond officer with some hidden secrets of her own, steps in to help Zenigata. Armed with their newly found information, Lupin, Goemon, Jigen, and Fujiko go back to “Drifting Island,” but this time they are followed by General Headhunter.

(Source: ANN)

It is a cross over between the series Lupin III and Detective Conan and takes place after the television special Lupin the 3rd vs Detective Conan. The plot follows Conan Edogawa who sets out to apprehend Arsène Lupin III, the suspect of stealing a jewel called Cherry Sapphire.

(Souce: Wikipedia)

The film will be a continuation spinoff of the 2012 "Lupin III: The Woman Called Fujiko Mine" television anime series.

Lupin and Jigen have their sights set on a treasure worth stealing called the Little Comet which is located in the country of East Doroa. The country has fortified its border after a singer named Queen Malta got assassinated in the neighboring country of West Doroa upon visit. 

Despite the two countries being enemies, Lupin and Jigen still plan to steal the treasure. During the heist, Jigen almost got killed by a skilled sniper named Yael Okuzaki. His specialty is preparing tombstones for his targets before executing his kills. Its said that no one has survived after Yael makes a grave for that target.

(Source: ANN)