After my previous research, I started designing a character in the style of the 1940s in photoshop. I did the entire drawing in black and white before coloring it with the different layer and filter options of the software.
Shown above, the black and white version of the character. I personally found that this design was ‘too old’. Although it is supposed to fit the 1940s, I believe that the character needed to be modernised a bit so as to appeal to an audience nowadays.
Here is the coloured version:
I kept the saturation quite low and tried not to have too many different hues. So as to embrace the film noir genre completely, the film should probably be entirely in black and white. Or perhaps there could only be one colour such as red or blue. (Although the idea of red has already been explored in the movie Sin City). If the film was to be shown in colour, then I suggest using a very desaturated colour palette so as to keep the cold tone of film noir.
I then went on to design a 1940s character based on the previous one, that I tried to modernise a bit. I explored a possible design for the dress with the colour of the moon (one of the three dresses the princess asks for in the original tale):
I once again drew the entire character in black and white before playing around with the colour. Perhaps the coloured version emphasizes the idea of the moon and the night. I am personally quite happy with the design as it is in black and white.
Here is the coloured version of this second design: