This is such a clever design! How did you make the little transparent window into Moby’s stomach?
Nice idea!
Question is: Is it Ahab or Jona?
As far as i know Moby Dick is based on an albino whale called Mocha Dick… so this might be even a look at Geppetto inside the big whale ? Especially when he is angling for food (?)
I used an empty in a texture coordinates node. Plug the Object socket into a vecor math node. Set the vector math to distance. Now you got yourself a mask in the shader, wich is controled by the emtpy position / scale.
You can tweak the falloff (how smooth or hard the mask fades) with a math node set to power.
I used the same principle for the alien in my space trains post. There i use it as a mask for the skin, to give the area around the nose and cheeks a blushing effect.
I don’t think Ahab survived!
Thank you for the detailed explanation! I’m excited to try this out 
Yes, remembering the story, Ahab wasn’t inside Moby Dick. His foot cot caught in the harpoon rope.
I didn’t think of Pinocchio though.