When I press 0 to go to my camera, everything is black.  I tried making a new camera.  Same thing.  The camera is angled properly and there is nothing in front of it blocking its view of my scene, but when I press 0, everything is black.  I can select one thing from camera view, a plane.  It appears that the plane is the ground.  When I press “g-key” to grab, I can move the plane, but it appears I am moving a dot, rather than a plane.  This is only in one .blend file, so it’s not a program issue...