Plagiarism in theory?

I write, obviously, since you're staring at 1's and 0's shaped into letters. But I am also a (very lapsed) freelance writer as well, being lucky enough to have sold some stories to be published back in the day. To avoid any hurt feelings on my end, I won't mention the day exactly, but Babylon 5 was still on the air. First run.

Anyway, let's say I had a hankering to get published but was fresh out of ideas. So I take some already published book, rewrite it using exactly the same plot and setting and characters, but simply change the names. (Cynically, I wonder if that's exactly how many books and TV shows are made today anyway, but let's ignore that.) I think just about anyone would agree that all I did was change minor things while keeping the story intact, and therefore my "book" was nothing more than a near carbon copy of the original.

So, when an Intelligent Design book is made by going back and replacing "creation" with "design", is this scientific (chuckle chuckle snort!) plagiarism or simply an admission that IDiocy is nothing more than creationism in a prettier costume? If you still say no, IDiocy is a real theory, than I'd like you to buy my new books, Moby Tom and Dick Sawyer. Coming soon, For What the Bell Tolls and Gone with the Breeze.