He grunted and lifted the Homeland Security case and flipped the lid. The crab’s control unit was a black handgrip with a digital display and a red button. He connected it to the tablet, followed the on-screen instructions, and pressed the button. There was a moment of stillness, then the crab stood, stretched, and scuttled up the door and through the crack at the top of the window. The display showed its rough location, and that it was moving fast. They exited the van and followed at a brisk run.