They scoured the oceans to bring us the most breathtaking imagery, never seen before behaviours and unforgettable creatures. They've used brand new, specially created cameras to bring us the very best films of our oceans we could possibly imagine. They've seen fish eating birds, octopuses outwitting sharks in ways we never thought possible and seen different species gathering together to hunt in cooperation with each other.
Now, they've been to the Cosmic Shed. Yes, that's right. They've finally made it. John Chambers (Assistant Producer), Sophie Morgan (Researcher) and Alex Vail join Maddy, Steve and Andrew in the Cosmic Shed to chat about the making of this stunning, landmark series.
We find out about some of the amazing technology they used to bring us the oceans like never before.
And reveal what it's like to spend so long among the wonders of the deep oceans.
They even deal with questions like whether turtles watch their footage...
So download the episode, put on your favourite headphones, sit back and imagine you're in the shed...or on location in the Pacific Ocean. The choice is yours.
During the episode, Andrew asked Sophie Morgan which behaviours she had found by reading scientific papers. Sophie told us that she had found something really remarkable which they had managed to film but she could not tell us what it was as it was embargoed at the time of recording. We can now reveal that Sophie's reading of scientific papers means that we can enjoy this stunning sequence of behaviour.
Many thanks to Mrs. Haworth's Year 8 Geography class at Haslingden High School for all your wonderful questions
All of the pictures (apart from the ones of Post-it notes) are provided by the BBC.
Update: Here's Mrs. Haworth's class listening to the episode in class. Best. Teacher. Ever.