The commercial broadcaster is paying £103.5m in cash for a 79.5% stake in Plimsoll, which was founded by Grant Mansfield in 2013 and has gone on to produce award-winning premium unscripted series for the likes of AppleTV+, Disney+ and Netflix, as well as a string of broadcast partners including ITV.

Mansfield, who was previously head of production company Zodiak in the US, MD of RDF and factual commissioner at ITV, will remain with Plimsoll together with chief creative officer Dr Martha Holmes, creative director Tom Hugh-Jones, head of factual entertainment Karen Plumb and head of documentaries Richard Klein.

The Plimsoll team will work alongside ITV Studios MD Julian Bellamy, UK director of unscripted Angela Jain and their team.

“The significant opportunities in the international premium unscripted market make this the perfect time for Plimsoll to join ITV Studios,” said Mansfield.

“There is a quite special strategic and cultural fit that will enable us to achieve our, now shared, creative and commercial ambitions for Plimsoll. We’re excited to be part of ITV Studios’ expanding global force in content and delighted that, from today, this powerful new partnership is officially active.”

“Growing ITV Studios with an exciting pipeline of premium programmes is core to our strategy as we further diversify the business by genre, by geography, by customer and grow ahead of the market,” added ITV CEO Carolyn McCall.

“Through Plimsoll Productions, as a studio, we can continue to capitalise on the growing demand for natural history and factual programming and I am really pleased to welcome Grant and the team.”

“Grant and the team at Plimsoll bring years of unrivalled experience in the creation and production of outstanding and award-winning natural history and factual programmes,” said Bellamy.

“I’m delighted to welcome them to ITV Studios – their addition to the group strengthens our position in supplying the best shows across all genres to buyers around the world.”

The ITV buy-out sees the UK broadcaster take over the majority share that Lloyds Banking Group’s private equity arm LDC took in Plimsoll three years ago, at which time the business was valued at £80m.

Mansfield, plus other members of management and strategic investors will retain 20.5% of the company, although ITV has the option to acquire that in time.

Magnify Media, the distribution business Plimsoll took full control of two years ago, will work alongside ITV in-house distributor ITV Studios, according to the companies.

Plimsoll is billed as the largest independent producer of natural history programmes in the world and is behind upcoming 6×60′ Stephen Fry-narrated landmark series A Year on Planet Earth for ITV, Tencent in China, Fox Nation in the US and ARD in Germany.

The company currently has 20 shows in production for a variety of broadcasters and streamers and counts among its other credits shows for the BBC, ABC, Channel 4, CNN, History and Hulu.

For ITV, the acquisition bolsters its factual credentials at a time when the genre is booming, with streamers set to expand into new areas including live programming.