At first when I saw previews for this episode I was saying how silly it seemed, but after watching, I'm quite impressed with how well it was done. Here's the overview.
Dean and Sam, both still not over what happened to Bobby, neither am I by the way but moving on, investigate a case where men are killed by being thrown against walls and then having both hands and feet cut off with a symbol carved into their chests. WHile working on the case, Dean goes to a bar where he meets a woman. THey engage in you know what and out pops a baby not even a day later. THree days pass and that baby has grown to a teenager. Come to find out, amazons are killing these men and as you can see, Dean is next on the list as well as Sam who is caught learning too much on the investigation. You see, these Amazons have others like them working in different fields, and one involves detective work. BOth Sam and Dean must fight to stay alive as they try to cope with the death of their father figure Bobby Singer.
Pretty bloody episode for a show with such a corny title, but its appropriate since they slice limbs off men. THe title is a reference to that girl group that existed many years ago, so you get the humor. THat's all.