Car won't start: No lights, No cranking, Nothing

A little background. I have my car stored down at a friends parents business. It's outside but under a large shed. Anyway went down to start it today and bring it home. I hooked up the positive battery cable and it fired over. I drove it probably 100 feet and shut it off to go inside and say hi to my friends dad. I came out and tried to start it back up and I got nothing. No crank, no headlights, no interior lights, nothing. I checked the wires going to the starter, which had voltage, battery was at 12.3 V, ground to the engine block was good.

I don't know whats going on and this kinda scares with the it not doing anything at all. All help would be greatly appreciated. Thanks guys.