This new location is well out of range of the dive boat. With the success of the shoot hinging on the diving, this is a worrying turn of events. The fishing boat motors on all night, taking the team further and further from their planned rendezvous. Our position now is three degrees... Eventually, the crew make contact with a passing fishing boat, and it's heading backin the direction of their dive boat. There is another boat out here, which is going on a much better course, so we're gonna transfer. It's a lucky escape for the team. The new vessel spends all day and all night motoring towards the new fishing grounds. 8.28 in the morning, and we've already discovered fish. Right out there, about 150 metres, the sea is frothing and boiling and that's obviously where the tuna are, so the ship is doing a circle round it and that's where they'll set the nets. It's all on, it's all on. Although it's a relief to begin filming, the real challenge is still to come. They need to get inside the net, and right now, that's not a very inviting prospect. But first, they need their dive boat to find them in this vast expanse. I can see our dive boat on the horizon. She's a little spec in the distance. Here we go again, ship transfer. There you go, that's our new home. See you tomorrow. At five in the morning, the fishermen are already setting the nets. It's time to take the plunge. It may seem a little strange why we're putting fishing net on our scuba gear, but it has a very useful purpose. These jagged edges of the gear are completely covered with this fishing net to prevent us from getting snagged and caught like fish. I don't normally wear a knife this big, but in this kind of situation, with all the nets around and the possibility of entanglement, it's a really good idea. This is a shark shield, and with a tuna-fishing boat, thousands of bloody tuna in the water, and a sea full of sharks, it could come in very handy. They enter the net. Despite having done all they can to prepare, this is a jump into the unknown. The scale of the net is breathtaking. They're relieved to find that there are no sharks this time. But there are also no fish. Frustratingly, days pass and the fishermen fail to find any more fish. We're going down to the wire here. We've got two days left and we still haven't seen any fish, so getting a little nervous. Yeah, it'd be tragic to be out here and not have the opportunity to film this. Eventually, they locate a school. So the question is, are there any fish in that net? This is the team's last chance to get the sequence. To their great relief, all their effort has finally paid off. They share the net with 150 tonnes of tuna - one of the biggest catches of the year. It's an intense experience.