Anything you can Do by Randall Garrett — Read

First of two parts. The Alien was _really_ alien -- and Earth was faced with a strange problem indeed. They _had_ to have a superman. And there weren't any. So.

Like some great silver-pink fish, the ship sang on through the eternal night. There was no impression of swimming; the fish shape had neither fins nor a tail. It was as though it were hovering in wait for a member of some smaller species to swoop suddenly down from nowhere, so that it, in turn, could pounce and kill.