On Loch Lomond in Scotland.

David's team is planning an ambitious sequence with swans, but filming animals is never straightforward.

- We want to film David with a group of swans flying alongside him as he goes along the loch in a in a boat, and it should be amazing - To do that, the team would need the help of some very accommodating swans and their handler Rose Buck.

- She has this extraordinary empathy with animals, and you can see a love and understanding of them -- and there of hers.

- For the sequence to work, the birds have to fly within 10 feet of the camera.

With Rose positioned just out of the shot and calling from the front of the boat, the flock begins to follow.

But the big challenge is to get David to deliver his lines together with the flying swans.

- They're doing their best and they're following you, but they don't necessarily understand exactly where they ought to be for the camera.

They behaved marvelously, but sometimes they don't realize that they should have been on the starboard side and they're on the port side.

I mean, it takes a long time.

- After several failed attempts, the weather turns for the worse.

The team has one last chance.

- Eventually the magic happened.

The swans absolutely hit it.

- When close up to a flying bird like this, you can see how the wonderful piece of complex engineering their wings are.

Able to change their shape and their beat to respond to every little change in the currents of the air around them, and so propel them forward and lift them upwards.

- David had brought another spectacular sequence to life.