A bestselling book about a homeless man’s heartwarming relationship with his cat is set to make it onto the silver screen.

The role of James Bowen, the author of A Street Cat Named Bob – who is currently looking at premises to open a cat café in Islington or Hackney – has gone to actor Luke Treadaway for the film adaptation, but the part of the famous feline is still up for grabs.

The Curious Incident of the Dog in the Night Time actor will star as the busker and former drug addict who credits Bob for “saving his life” after he came across the moggy in 2007 while living in sheltered accommodation and selling the Big Issue magazine at Angel Tube.

Bob, who had been attacked by another animal, needed help – and James slowly nursed him back to health, turning his life around and putting the cat’s needs above his.

A few months before the pair became acquainted, James, who chronicles his experience in his debut book, and its sequels, had suffered a troubled past – homeless and living hand-to-mouth.

When Bob recovered, James sent him on his way, expecting never to see him again. But Bob had other ideas and began to follow James everywhere he went.

The pair shot to fame after videos of James and Bob busking in went viral, with the book series following shortly after.

Earlier this year, fans donated thousands to help James finance a café to look after vulnerable cats and support adult literacy projects.

The film production is set to begin a seven-week shoot in the UK from late October. Ruta Gedmintas will co-star and directing the film is Roger Spottiswoode, of Tomorrow Never Dies, from a script written by Tim John.

Adam Rolston will produce the film for his new venture Shooting Script Films in what will be the company’s debut release.

Speaking about the film, James said: “It is amazing, I think, to have somebody make a film about you – let alone at the age of 36.

“Bob just takes it in his stride. It’s been incredible and I’m very thankful to Adam for purchasing the rights and Luke for taking up the part to play me, so that should be interesting.

“I believe Luke and I will be spending some time together and it is going be crazy to see some of the action when it is being filmed.”