Hakugei volume 2
Ahab just seems too personable, too buddy-buddy, for a true Moby Dick interpretation. He's like a Captain Harlock. They talk about him and say he has "personality defects" but they still love him.
The detective White Hat is "looking for the big one [criminal--Ahab] that got away." Detective White Hat whipped him in prison and after Ahab escaped, he went looking for him. Ahab seems to have more reason to go after White Hat than the white whale. Now amazingly, he joins the crew and they are all buddy-buddy.
Then they are having little side adventures while still pursuing their ultimate goal. So that is a lot like the novel Moby Dick. However, I am liking this anime series.