In this series the challenge for two groups is to build mega machines, which will be judged by Jamie Hyneman and Adam Savage. This episode of Discovery Channel’s ‘Unchained Reaction,’ December 7 at 9 p.m., has a team of multimedia artists taking on a group of metal workers to engineer the ultimate multi-step machine with explosive results.

The ‘Gator Boys’ (season 18) are Paul Bedard and Jimmy Riffle, alligator trappers. In the episode, ‘Warrior Gator,’ December 9 at 10 p.m., Paul gives a triple-amputee the chance to wrestle an alligator. Then the duo capture a gator at a farm and one that’s been stalking people in a neighborhood pond.

In ‘See You Later Alligators,’ December 12 (same time), rumours abound that Everglades Holiday Park, the home of Paul and Jimmy is at risk of being closed. Could this mean the end for the Gator Boys?