Britt Allcroft, who has died aged 81, brought the Rev Wilbert Awdry’s adventures in his Railway Series of books to television in Thomas the Tank Engine & Friends – and turned it into a global phenomenon earning her millions of pounds.

She read the books, first published in the 1940s, while making a 1979 Central Office of Information film about a resurgence of interest in steam railways, which included interviewing the locomotives’ creator and filming on the Bluebell heritage railway in West Sussex.

“It really didn’t take me long to become intrigued by the characters and the relationships between them, and the simplicity of the stories,” she said. “I was equally intrigued by the illustrations, the landscape in them and the nostalgia they evoked.”

The experience also triggered childhood memories of her Auntie Tro travelling from London to see her in Sussex, where Allcroft would greet her with the words: “Tell me what happened on the train today.” Tales of people and adventures woven around the journey followed.

In 1980, she formed Britt Allcroft Railway Productions (renamed the Britt Allcroft Company four years later) with her then husband, Angus Wright, a television producer and director, snapped up the TV and video rights to the Railway Series for £50,000 from the publisher, set about adapting the stories herself and then spent almost four years raising finance for the productions – even mortgaging their house.

Finding a narrator was made easy for Allcroft when she heard Ringo Starr, the Beatles’ former drummer, being interviewed on television. “I thought, ‘That’s the voice of Thomas’s storyteller,’” she said.

The programme, with Allcroft as executive producer and David Mitton as director, began with a 26-episode series on ITV in 1984. Alongside the cheeky blue steam engine Thomas and different-coloured locomotives on the island of Sodor, including Gordon, Edward and Henry – all live-action models – was the Fat Controller, who owns the railway and was later renamed Sir Topham Hatt for the American market.

Michael Angelis took over as narrator from the third series, completing 10 runs in 2012, and accusations of sexism led to the introduction of several female characters from Awdry’s books in the fourth series.

Thomas the Tank Engine & Friends (retitled Thomas & Friends in 1999 and switching to CGI animation in 2009) ran for 24 series until 2021. The five-minute episodes were screened in more than 150 countries. In the US, they were originally broadcast in pairs as part of the live-action children’s series Shining Time Station (1989-93, plus specials in 1995 and 1996), which Allcroft devised with Rick Siggelkow.

Profits for the Britt Allcroft Company had reached £6.3m, on a £53m turnover, by the time it was launched on the London Stock Exchange in 1996. The business by then also had valuable Thomas the Tank Engine merchandising licences, and in 1998 bought the books’ copyright and also secured rights to make Sooty and Captain Pugwash programmes.

Allcroft then wrote and directed the 2000 feature film Thomas and the Magic Railroad, but its poor performance at the box office led her to resign that year as deputy chair of the company, which was renamed Gullane Entertainment and announced that she would remain its “creative cornerstone”.

HiT Entertainment bought the company in 2002 for £139m and, several months later, Allcroft stepped down as executive producer of Thomas & Friends. The business passed on to the American toy giant Mattel in 2012 as part of a $680m deal.

She was born Hilary Mary Allcroft Coote in Worthing, West Sussex, to Jessie (nee Harrison), an artist, and David Coote, a Russian-Jewish naval officer who walked out on the family when she was five.

She attended the town’s high school, then took a secretarial course at Worthing college of further education. While there, she was one of the teenagers who successfully auditioned to interview celebrities such as Kenneth More and Tommy Trinder in the 1960 BBC radio series Let’s Find Out.

Two years later, she appeared in The Sunday Break, an ITV “pop-religious” show giving a voice to teenagers. Her work as a secretary, meanwhile, included jobs in the Worthing Gazette’s advertising department and the town’s museum and art gallery.

She came to the attention of the ITV company Southern Television in Southampton when in 1963 she twice appeared on the pop panel show Dad, You’re a Square, with teenagers taking on their parents to vote “buy” or “break” for new releases.

The following year, the station gave Britt Allcroft (which she used as her professional name) her big chance as a presenter alongside Fred Dinenage in Three Go Round, a youth magazine show. She appeared in the 1964 and 1965 series, directed by Wright, whom she married in 1977.

Going behind the scenes, she switched to the BBC to join the production team on Blue Peter (1966-67) and even had the chance to present a spin-off, John Bull. It was intended to appeal to the 12-plus audience, with Allcroft and Terence Edmond in the studio and John Noakes on location, but the programme never made it past an untransmitted pilot.

More successfully with the BBC, she devised two quiz shows, Get It – Got It – Good (1967) and Moon Clue Game (1968), also presenting the second.

After a trip to the US to research American television, she returned to Southern Television as programme organiser on Junkin (1972-74), helping to make some of the all-female studio audience’s dreams come true in John Junkin’s afternoon show.

She later produced Dance Crazy (1979) for ITV and both Mothers By Daughters (1983) and Fathers By Sons (1985) for Channel 4 before concentrating on Thomas the Tank Engine.

Allcroft’s other animated success as a producer was Magic Adventures of Mumfie (1994-98), based on Katharine Tozer’s 30s books featuring an elephant. In 2022, after she bought back the rights, it was revived as Mumfie.

Allcroft’s marriage to Wright ended in divorce in 1997. She is survived by their daughter, Holly, and son, Ben.

• Britt Allcroft (Hilary Mary Allcroft Coote), producer, writer and director, born 14 December 1943; died 25 December 2024