A Big Hole Underneath
Gabby sensed that they were getting closer and closer to the finish line. Then, as the last scoop of muck was removed by one of the officers, a large hole was discovered that extended all the way beneath the headstone of the burial. But, since the dirt had been taken from one side of the stone, it was now possible for the stone to fall through the ground with just one incorrect move.
Reaching Inside
They were aware that they needed to move quickly. One of the officers dropped down on the ground and stuck one of their arms inside the opening. He moved his arm around in an attempt to get a sense of what was under there, but the hole was too deep for him to feel anything. He did not feel anything until he put his whole arm and shoulder into the hole. Only then did he realize there was anything there.