
Behind the scenes: Filming underwater —
A CNN crew boarded a support vessel in the North Sea for a demonstration of remotely operated vehicles. Producer James Frater, pictured, describes the thrill of dragging heavy gear around a huge vessel in heavy seas.

Behind the scenes: Filming underwater —
"The calm conditions that had allowed us to easily film inside the port quickly changed once we left the harbor, as we came up against 25-knot winds, rolling waves and spray soaking us from all sides," says James.

Behind the scenes: Filming underwater —
James: About 2 miles (3 kilometers) out to sea, between the waves, we got fleeting glimpses of the MV Olympic Triton, the support vessel for remotely operated underwater vehicles. We could tell it was large, but as we drew closer to the 315-foot (96-meter) vessel it became clear it was not only large, but a serious piece of maritime engineering.

Behind the scenes: Filming underwater —
"As we approached the Olympic Triton, conditions were too dangerous for us to board and we had to wait for the massive vessel to turn to give us a bit of shelter. While waiting we filmed our first key sequence: the ROV being lowered into the water."

Behind the scenes: Filming underwater —
"Sheltered from the worst of the weather we were still rising and falling in the water by as much as 10 feet. To board, we had to wait for the bow of our boat to rise up and then throw ourselves at a small wood and rope ladder and hanging grab rope and pull ourselves aboard."

Behind the scenes: Filming underwater —
"We only spent a short amount of time with the talented crew of the Olympic Triton, but we did get a sense of how good they are at what they do, and how incredibly difficult their work is."