The head-scratching genius of Murder on the Orient Express will compete with the genre-changing twist-in-the-tail of The Murder of Roger Ackroyd, when the estate of Agatha Christie launches a quest to find the best-loved novel by the queen of crime.

Famous fans of Christie’s including David Suchet, who played Hercule Poirot on screen, and Sophie Hannah, who wrote an authorised Poirot novel story, The Monogram Murders, are championing their own favourites as part of celebrations to mark the 125th anniversary of the crime novelist’s birth. More than 80 books are in the running to be named the world’s favourite Agatha Christie novel, and the public vote was launched online on 27 April.

Suchet, backing The ABC Murders, said he was “bowled over by … the plot”, describing the book as “one of Agatha Christie’s very best novels, [which] showcases the genius in her ability to produce so many novels about one detective, and yet come up with so many storylines”.

Crime novelist Val McDermid plumped for The Murder at the Vicarage: “I defy anyone really to understand the mechanics of writing crime fiction without going back to Christie,” she writes, “and in particular without going back to The Murder at the Vicarage. You could say in many ways that that one book is responsible for my entire career.”

Hannah went for After the Funeral, fellow novelist Kate Mosse chose Sleeping Murder, while David Baddiel is rallying support for The Murder of Roger Ackroyd and Christopher Biggins for Death on the Nile. Christie herself, writing to a Japanese fan in 1972, had said that Endless Night was “my own favourite at present”, while The Murder of Roger Ackroyd was “a general favourite”. She added that she liked And Then There Were None for “a difficult technique which was a challenge”.

Her grandson, Mathew Prichard, threw his support behind Endless Night, saying of the vote: “It’s exciting to see, almost 40 years after her death, that my grandmother’s books are still so popular. Her fans come from around the world and from diverse walks of life, and we’re looking forward to hearing from them wherever they are. I’m intrigued to see which book unites them as their favourite.”

Christie’s books have sold more than 1bn copies in English, with another billion sold in foreign languages, according to her estate. Her first novel, The Mysterious Affair at Styles, was also the first to feature Belgian detective Hercule Poirot, and was published in 1920.

The winner of the public vote will be announced in September, the month of Christie’s birth.