You have 5 minutes to hide a paperclip in your home. A detective has 24 hours to find it, If they don't, you get $100,000. Where are you going to hide the paperclip?
Straighten it, open an electrical box, and slip it into the wiring where the ground wire is. Metal detector wouldn't really find it, it would just blend in the the metals around it. It wouldn't be obvious, there would be no holes around it, you wouldn't need anything more than a butter knife to hide it. And if you were careful, your house wouldn't even burn down.