At the beginning of August I found myself standing on a dock in Plymouth, staring at a 72ft-long expedition yacht called Sea Dragon, wondering whether I had been wise to take on this job.
A few months earlier I’d been sitting in my office in New York when the phone rang.
It was my boss.
“There’s a project I think you might be interested in,” he said.
Would I like to go on a month-long sailing expedition around the UK to find out more about the plastic in our oceans?
Would I mind if it was with a group of strangers?
Could I film it?
Could I make it into a documentary?
Maybe it would be a nice break from covering Donald Trump.
I said yes.
And then suddenly, it was happening.
I couldn’t really sail, not in the open ocean.
Nor could I really film, not even on dry land, let alone on a boat.
So my knees wobbled a bit as I boarded Sea Dragon and found my bunk.
I was right to be nervous.
To start with it was lovely.
We got a warm welcome from Emily Penn and Lucy Gilliam, co-founders of Exxpedition.
Their organisation runs women-only voyages that aim to raise awareness of plastics and toxins in our seas, and turn those who take part into the best possible advocates for ocean health.
They’ve sailed all over the world, but both felt it was time to bring their cause home to the UK.
Our brilliant professional crew; skipper Diane Reid, first mate Holly Vint and deck hand Kat Law, ran us through the sailing basics.
Life jackets fitted, gear stowed in tiny lockers, go-pros charged, we set off from Plymouth in high spirits.
Then we started throwing up.
Woman by woman, the crew went down.
Through the ocean we rolled, into the wind, around Land’s End.
It was like being in a washing machine.
We ran out of spaces and places to vomit.
Our professional crew knew it was coming, they had seen the forecast.
They waited patiently and with sympathy as we retched and cried and wiped our faces.
They put some of us to bed and encouraged some of us to power through it.
It was the hardest thing I’ve done in a long time.
But we made it to our first stop in Cardiff feeling less like a group of strangers and more like a team who’d faced adversity and come out the other side.
As oceans advocate and sailor Emily Penn put it to me, rising to difficult challenges is part of the point.
The health of our waters depends on it.
And so our journey continued.
We zipped across the Irish Sea as shooting stars danced above us and dolphins played at our bow.
We motored under Tower Bridge, shared stories and meals, hoisted sails and ground winches.
I started to understand why people get hooked on sailing.
But at times it was far from joyful.
It felt as if we were being stalked by plastic.
A piece of what looked like food packaging got sucked into a water filter and nearly stopped our journey.
We found clumps of balloons in the North Sea as we were searching for a diver that had gone missing.
It was so sad to look for a human and find plastic instead.
We seemed to pull the material out of every trawl we did.
Sometimes it was microfibers only visible under a microscope.
But some of the samples, especially from the Thames, were crunchy with micro-beads.
It came up in the sediment we dredged from harbour bottoms.
It was in the guts of an eel we found in our engine.
It was everywhere.
The act of bearing witness had a profound effect.
Suddenly, we didn’t know about the problem because we’d read an article or seen it on Instagram, we knew because we’d seen it with our own eyes.
Management consultant Deborah Stott said simply “You can’t un-know this. We have to act.”
The discoveries gave our public outreach efforts in port a new sense of urgency.
At every place we docked, the crew tried to convince people to stop buying single-use plastic.
We picked up litter from beaches and river banks, hearing it creak and snap under our feet.
We listened to our land-based ambassadors Amy and Ella Meek plead with people to get “plastic clever” by replacing bottles, coffee cups, straws and bags with reusables.
We met politicians, put on art displays, performance art at the Edinburgh Fringe… you name it, this crew of women tried it.
It was genuinely inspiring to be a part of such an ambitious effort.
It was also refreshing to talk to people honestly about how we can tackle the problem; how individuals can choose to consume differently, how big business needs to respond to the design challenge, and how policy makers must help us move in the right direction.
As crew member and writer Sarah Tanburn said to me, change is never perfect, and incremental progress is infinitely preferable to none.
The women on board Sea Dragon left with this ringing in our ears.
We’ve returned to our families, friends and communities with a new understanding of what’s at stake.
The alterations we make to our lives as a result won’t be perfect, or enough, on their own.
But we’re going to try.
You can, too.
:: Watch A Plastic Voyage on Sky Atlantic at 9pm on Tuesday and on Sky News on Wednesday at 9pm.
:: To get involved in our Sky Ocean Rescue campaign, visit the website here.