So far, so good..
So far this is good. Very good. I would love to play the final version. There are some problems I had though, and they are as follows.
Firstly, there was the music. Not that the music was bad by any means but it wears on the ears seeing as it often loops and plays through every room only really changing during a couple scenes. I admire you using a jazzy soundtrack let alone one from the show but you should pick something that either fits a loop better, or you should have the music differ from each room and scene. Preferably something that fits a scene better in context to the events happening on screen.
Secondly, there's the way the speech runs. Pressing space bar to keep the text moving was a bit awkward. I suppose you added this so that slower readers could keep up with the text boxes, however it got a little annoying to have to keep pressing space bar. I'm so used to the fact that the text continues automatically that I would click around and nothing would work because I forgot to finish a conversation with space bar. In old SCUMM based games they gave the player the ability to choose how fast the text goes by, you should add in a function like that. If that's complex just add the option for people to actually press space or to have it flow automatically for those who don't want to hit space like myself.
This last one is arguably the pettiest of my gripes, but seeing as I am an English majour I should mention it. The grammar was at times poor. Things like "In the meanwhile, in the deep carribbeans" is horrendously improper. First of all Caribbean should only have one R, and it should never be plural. Also it should be "Deep in the" not "In the deep." Also remove "In The" from "Meanwhile" as well. You used "Carribeans" again later.
Under the files you also say that Inspector Zenigata is an "Investigator of Interpol." So he investigates Interpol? It should state that he is "An investigator for Interpol" or "An investigator working with Interpol." He also says he is an "Investigator of the Interpol" in the intro, which makes the same verbal mistake as saying he is an investigator of Interpol.
I hope I'm not sounding rude on the last part but when writing a story based game you should have better form with whatever language it is you are writing the story in. If you wish, I would be willing to help you revise and edit the script so it is a bit more proper before the final game comes out.
I enjoyed it though! It was funny and as a fan of both Lupin the Third and Monkey Island I am glad to see that you are doing both series a bit of justice whilst still setting up some of your own ideas. The puzzles weren't bad, not too easy but not too hard either and they had logic behind them.
Would love to see the final project. :)