Not underrated in that it is appreciated by those of us who get it and I'm not sure Anderson was aiming for more than that, it's certainly the most extreme of his pictures. I imagine that if you liked his first three pics, you'll love Aquatic because it's a distillation of his style to a theatrical otherworldliness rarely seen in cinema outside science fiction (a New Zealand film called Desperate Remedies is another example of this).
Mind you, I think The Darjeeling Limited is fantastic, but am seemingly alone in this.
