Shark Week continues on Discovery with two more prime-time premieres with bite. At 10 p.m. ET, the network presents Monster Hammerhead, which brings to mind that soothing old folk tune (“If I had a hammerhead…”). And before that, at 9 p.m. ET, Discovery presents Jaws Strikes Back, a new documentary showcasing the technology of and images from a new robotic underwater vehicle called, of course, the SharkCam. For those who remember David Letterman’s MonkeyCam, this hardly seems like a major advancement. But to at least one great white that encounters the SharkCam, it looks more like a SnackCam.