I ranked it as #8. Though not without its problems, it is a strong episode. What I found particularly effective was when Kirk starts, rather hesitantly and unenthusiastically, to try to defend Charlie to the aliens who've come back for him. Even going so far as to say that the boy should "be with his own kind." Charlie, of course freaking out and everything. I don't know why I liked that so much. I guess because it does show the kind of leader that Kirk is. He has every reason to want Charlie off his ship and wrapped in heavy chains, but instead, tries to show mercy, however futile he knows this might be.