British author Jilly Cooper, celebrated for her popular and daring novels like “Rivals” and “Riders,” has passed away at the age of 88, as confirmed by her agent and family on Monday.

A statement from her family said that the author’s “unexpected death has come as a complete shock.”

Cooper gained fame through her series “The Rutshire Chronicles,” which delved into the indulgent lifestyles and romantic adventures of the affluent, horse-riding elite in 1980s England. Her books achieved impressive sales, with millions of copies sold in the UK.

One of the books, “Rivals,” was turned into a hit Disney+ TV series last year starring David Tennant and Alex Hassell.

Her agent, Felicity Blunt, expressed in a statement, “The highlight of my career was collaborating with a woman who has influenced culture, literature, and dialogue since her first publication over fifty years ago.”

Blunt further noted, “Jilly is widely recognized for her best-selling series ‘The Rutshire Chronicles,’ featuring the captivating and daring show-jumping protagonist Rupert Campbell-Black.”

Born in 1937, Cooper cut her teeth in journalism at a local newspaper in Brentford, covering everything from parties to soccer.

Cooper’s career took a significant turn in 1969 when The Sunday Times featured her story about her experiences as an “undomesticated” homemaker. This led to a column that ran for more than 13 years, later followed by another column in The Mail On Sunday, which lasted five years.

Her first book “How to Stay Married” was published in 1969.

Cooper’s many fans included former British Prime Minister Rishi Sunak, who said the books offered “escapism.”