How do I retrieve a detached plunger from a bathtub drain?
Unfortunately, I think you're fixin' to go for a crawl with the crawlies. (At least you have that option -- the same task in my house would require a jackhammer.) There SHOULD be a P-trap below the drain. If you can get the tailpiece off of the bottom of the tub (unscrew the metal drain, then the tailpiece should pop out), you should be able to spear the plug.