When I heard the premise of this film, I was not looking forward to it. As much as I enjoy prequels like "Batman Begins" and "Casino Royale", I really didn't need the backstory behind Lupin and his gang. I had no interest in seeing flashbacks of how the group got together. Thankfully, I was wrong about this film.
Ignoring all the prequel elements of the movie, this is a really solid Lupin III adventure. It has the right balance of all its major characters. Fujiko is used to her fullest, Goemon brings in some great energy, Jigen has a crucial character arc and even Inspector Zenigata has important story beats. The movie does a good job of showing how these people work best when they are all together.
The story has a memorable villain and henchmen. They have the right level of personal stakes and physical intimidation.
The prequel elements are also handled quite well. Without going into spoilers, it ends in such a way that leaves you asking, how much of that was even real?
Going in with zero expectations, this turned out to be one of Lupin's best adventures.