The Duke of Sussex has a few things going on at the moment. There's the upcoming tour of Africa, the charitable foundation to launch with his wife, the campaign he is doing with the military and then, of course, the not-so-small matter of new parenthood.
But the thing that is occupying much of Prince Harry's headspace right now is mental health.
His own, of course, but also everybody else's, and how much better life is when you look after it. It is the narrative that runs through absolutely everything he does, a subject he is so passionate about that he is currently working on a groundbreaking new documentary series on it with Oprah Winfrey, details of which the Telegraph is able to reveal today.
The series will focus on breaking down the stigma and shame surrounding mental illness – showing examples of the "human spirit fighting back from the darkest places," as the Duke puts it. Alongside Oprah, he is co-creator and co-executive producer on the venture, which will launch on the new Apple TV+ streaming service next year.
It is a matter of great importance to the Duke that he gets this right – that the series is meticulously researched and based in fact and evidence, as well as being human and relatable, too.
"When I did your podcast two years ago," he tells me, "the response made me realise what an impact sharing my story could have, and what an impact other stories can have for so many who are suffering silently. If the viewers can relate to the pain and perhaps the experience, then it could save lives, as we will focus on prevention and positive outcomes."
This is an endeavour, he is keen to add, that is born out of much research.
"We are assembling subject matter experts as an advisory board to the series, the main reason being we appreciate this is a multi-faceted subject – and we have a huge responsibility to get this right.
"In this process, I've already learned just how many studies have been done, and how much information is out there which isn't reaching the general public. The facts and science exist, and we deserve to know it all."
In a world where high profile people hitch themselves to causes such as mental health out of a desire for publicity rather than change, the Duke's genuine dedication to the cause is both exciting and refreshing.
He understands instinctively that mental health is not a single issue, but rather one which underpins almost every other issue.
As he told me in Kensington Palace in 2017, when we sat down for our podcast chat about his own mental health, and how close he came to a breakdown after the death of his mother, it is the thread that runs through all of the young royals' charity work.
"Whether it's homelessness, whether it's kids and early intervention stuff like that, and obviously my connection with the veterans… everywhere we go there is a conversation that happens with someone that we've spoken to that links it into a mental health conversation of sorts. It [mental health] is linked into so many different things… the experience I have had is that once you start talking about it you suddenly realise you're actually part of quite a big club."
And once he started talking about it, he realised that there was no escaping the very real need to carry on talking about it.
At a recent event for the mental health crisis text line, Shout, which was launched as a legacy of the royals' Heads Together campaign, the Duke asked me when we would next be doing a podcast about the stuff in our heads. "We could do it right now?" I only half-joked. But his message to me was clear: there is so much more to say on the matter, so much more to do.
While recently it has been suggested that the Duke has been seduced by a life of glitzy holidays, his real work often takes place in a tent in Africa, which he considers his second home – running his HIV charity Sentebale, pursuing his passion for conservation.
He also carries on his mother's work in demining – next Thursday, the fourth day of the Sussexes' Africa tour, he will travel alone to Huambo, Angola, to visit the location where she was photographed in the months before her death in 1997, prompting worldwide efforts to restrict the use of mines in war.
These are the things that ground him – working as hard as he can to maximise the opportunity his position gives him to make a real difference to the causes close to his heart.
Traditionalists may not like it, but his almost unique ability to connect with the public is undimmed, and he is still the most popular royal after the Queen.
His commitment to talking about mental health, and more importantly his natural empathy around the subject, is at the heart of this.
Two years on from the podcast we recorded together, it is easy to forget how genuinely groundbreaking his admission of being close to a "complete breakdown" was.
As part of a family that had long reigned with a stiff upper lip, his openness was a watershed moment and gave many people – and in particular, young men – permission to say the previously unsayable.
But that merely marked the start of the conversation, and it is one that the Duke is far from finished with – be it via his work with veterans through Invictus, his support of the crisis text line Shout, or this new documentary project for Apple.
When he met Oprah Winfrey, and realised their shared passion for mental health, the idea for the series was born.
And he has been hands on ever since, with the Duke hosting numerous meetings in London with Oprah, and helping to select the creative team behind it, which was announced on Monday evening.
The series will be helmed by Kahane Cooperman, who produced The Daily Show with John Stewart in the US, and feature episodes directed and produced by the likes of Dawn Porter, an American filmmaker who has created documentaries about segregation and anti-abortion laws, and Asif Kapadia, who was behind the Oscar-winning documentary Amy, about Amy Winehouse, and the Bafta-winning feature Senna, about the life of the late Formula One driver Ayrton Senna.
Both films were acclaimed for their intimate and moving portrayals of people whose lives had previously been shrouded in mystery.
Like so many campaigners, the Duke's work in the sector is linked inextricably with the way he lives his life personally.
"I'm very much still on my own path," he says. "What I have learned and I continue to learn in the space of mental health, mental illness and self-awareness is that all roads lead back to our mental well-being, how we look after ourselves and each other."