Catch up TV on Marine Machines. Watch the latest and all other episodes of Marine Machines now online, broadcasted on 7Two. Catch up on your favorite 7Two TV show: Marine Machines. Replay tv on its best! The Earth's oceans, which cover more than 60 percent of our planet, are ominous and unpredictable. This fast-paced series reveals how creative individuals use extraordinary tools to overcome the challenges of the Earth's vast final frontier and discover, explore and work in these extreme conditions.