The other day, I was taking a nap on the couch with the TV on. About an hour later, I woke up to this scene on my television screen. The show looked just like one of those nature documentaries (I just love those). If you follow the link to the video, you can see how realistic the sea scorpions looked, and would never have guessed that they are a complex synthesis of CGI and models. Nigel Marvin does some very believable acting when faced with not only these viscious critters as well as a wide variety of sea monsters.
I was fixed to the screen, wondering where on Hell on Earth this place was, where these sea scorpions actually lived. Nigel later takes a swim with what looks like an ancestor of modern day octopus, and the special effects are breathtakingly realistic.
I didn't realize I had been had until the scene where he does a time warp and walks a few billion years into the past. I figured by then that the documentary was more drama. But it was still excellent.