Calvino Noir is fun but also has some severe flaws.
The art style, music, narration and voice acting are all good ( bar Siska's ), and they blend in rather well. You quickly get use to the greyscale art style, where some colour is only added to help attract your attention to certain objects and places.
Even in some cases the colour can be rather subtle, like a hint of soft yellow in a sea of grey.
The story isn't bad either, although some of the dialogue can be rather cringey at times. This is mostly due to the fact that it's a Noir game set in the 1930's.
The main issues are the checkpoint system, and the character movement mechanics; and that it seems to have been designed for iOS and tablets first. As a result you need to do everything with a single mouse click. You move with a click, you stop, you open doors, select items, and change characters that way.
There are no real options either.
Some parts of the game can easily take 30+ minutes and accidentally dying or being spotted because of the slow character movement and clunky system is horrible. As the checkpoint saves can mean you're suddenly set back that 30+ minutes.
It's extremely annoying, as the characters can't make turns or go up and down stairs rather well. They walk, stop, turn, stop, then move. In that time the guards would easily have spotted you and shot you. They are rather trigger happy, as they shoot the second they see someone.
If you can get by the controls and checkpoints the game is rather enjoyable. Especially if you like stealth Noir games. It's rather fun.