Never have the contents of bookshelves been scrutinised with more gusto. For nearly a year, bored Zoom users have scanned the titles artfully arranged behind colleagues or friends — a duty performed for public figures by the Twitter account Bookcase Credibility

It launched last April to track, rate and assess volumes spotted behind talking heads with the tagline, “What you say is not as important as the bookcase behind you.”

Sometimes it’s intriguing — what exactly was in the small black case among the books floating behind Tom Hanks’s head? Otherwise, there are gotcha moments: the shelves of Amazon founder Jeff Bezos bereft of books perhaps, or Holocaust denier David Irving’s work spotted chez Michael Gove. Or it could simply confirm expectations: Prince Charles’s shelves show he is partial to equestrian topics.

Last year bookshelves became a beacon into the soul — or at least, the image their owner arranged them to convey. When it comes to deploying this skill, though, one man has a decade’s head start on the rest of us: Stephen Foster. He owns and runs Foster Books in Chiswick, west London, an independent shop that has been in his family for close to five decades.

It has long specialised in old or rare books and first editions. But in the past 10 years or so, Foster has carved out another speciality: movie librarian, the man who curates the shelves in films by Mike Leigh, Jane Campion or Guy Ritchie.

Some free advice from Foster in advance of that next Zoom session. “The key is authenticity, about making things feel as real and in place as they can be. If nobody notices [the bookshelves on a movie] you’ve done a good job,” he says. “The same logic applies with Zoom calls. If I have a bugbear it’s the people who are trying too hard — turning the book so the front board is out.”

Politicians are most prone to this, keen to signal their intellectual heft with front-facing biographies and their well-thumbed Dan Browns concealed behind them. Writers are their antithesis. “Their shelves often seem very genuine: these are their tools, and they are comfortable with them in their surroundings.”

It was Charlotte Watts, an Oscar-nominated set decorator, who first opened up this niche to Foster. She came to his shop in search of an elusive volume by Keats while working on Campion’s Bright Star (2009), starring Ben Whishaw as the poet. Watts asked about a book that Keats had published to little acclaim and low sales, which they hoped to feature. Could Foster track one down?

It’s very expensive, he explained, but he did know of a facsimile, and could likely have one custom-made using paper much the same as that in use 200 years ago. “And we ended up doing the set dressing,” he says. “We’d always sold the odd book to prop buyers, but that was when we started to supply the hero items, those which are handheld, or scripted, and you really need to get right.”

Since then, largely thanks to word of mouth, Foster has worked on eight or nine TV and film productions each year, whether kitting out a room in era- and character-appropriate titles, or hunting down a rare book required by a script.

He is distinct from a prop house, many of which also rent out books; they are often charged by the metre. Foster is more painstaking: steering the producers of The Crown to use the right parliamentary papers, or dressing shelves with period and character-appropriate books in The Danish Girl.

Thanks to Foster, one character who would likely earn a top rating from Bookcase Credibility is James Bond. Look at the bookshelves in Skyfall or Spectre, and it is clear the agent is a discerning reader.

No wonder he would pick books by travel writer and adventurer Patrick Leigh Fermor, who was also special ops. A history of the Scottish highlands shows how much Bond’s heritage matters to him, and the glossy tome on Aston Martin is hardly surprising. Squint closer, though, and you might even spot Birds of the West Indies, written by one James Bond — a book owned by Ian Fleming, and from which he cribbed 007’s name.

Foster had initially had another idea, though: “We’d done all the books on [Bond spoof] Johnny English about three months before, and had them all boxed up and ready. I did wonder if anyone would spot if we just used those.”

Set in the 1920s, the script for Mr Holmes — starring Ian McKellen as Sherlock Holmes — called for him to turn to a book of colloquial Malay. “I was surprised when I found one,” he says. “It was called Colloquial Malay and published in 1923.”

But even Foster could not fulfil the brief for another Sherlock Holmes — the knuckle-dusting 2009 version directed by Guy Ritchie and starring Robert Downey Jr. He was warned that the A-lister would only work with originals, not replicas.

The problem was that the script required Holmes be thumbing through an oversized ornithology book from the high Victorian era. The only suitable one available at the time was The Birds of Great Britain by John Gould, worth £50,000 and too delicate and valuable to borrow. Instead, Foster helped the art department create a custom fake that even Downey Jr couldn’t disdain.

Another customer is Disney, whose creatives have tapped him to work on its live-action cartoon remakes, such as Cinderella and Beauty and the Beast. Many of these stories derive from the writings of Charles Perrault, a 17th-century author, so require books that evoke that periwigged period. B

ookish Belle gets lost in a library at one point during the latter movie; her surroundings resemble the classic library that so many Zoom users seem keen to evoke on their at-home shelves.

They’re primed to fail miserably, as Foster explains. “It quickly became apparent that the size of the library she was going to get lost in would be too expensive and impractical to do with real books, so they decided to do CGI — we supplied some very pretty 17th-century bindings, and they took good photographs of them then turned them into the grand library you saw.”

Foster’s brief for the upcoming live-action Little Mermaid was different. “We had to supply books that weren’t such good quality, so they could be barnacled with all sorts of stuff for Ariel’s library under the sea.” Thankfully, though most producers prefer to rent titles, Disney always buys whatever it uses, he says, probably in case those props need to be repurposed at theme parks or similar.

The rise of high-definition cameras has underpinned his business, as it has nudged production designers into ensuring every on-screen detail is correct. The convenience of his location has helped, too; Chiswick is close to the Golden Triangle in west London where production facilities, like prop houses, once clustered to be near the former BBC studios, Elstree and other studios.

Foster’s temperament has also been a factor. “Booksellers can be grumpy, especially about borrowing books, but because we were amenable, word got out,” he says. “I’m not going to fob them off with something that’s not right just to make money.” (He declines to name exact fees, noting that the amount charged depends on the title, length of loan and the film-maker’s budget.)

Foster has expanded into working with museums, helping with historic tableaux — at the just-renovated Audley End in Essex, he helped English Heritage fill the children’s nursery with many of the books that the house inventory suggested had been there in the 1830s. English Heritage also hired him to fill the bedroom shelves at Darwin’s House, using the scientist’s own records of what he owned as a starting point.

Otherwise, 2021 has been quieter than usual, thanks to pandemic-induced production shutdowns, although Foster has a few projects under way, including Disney’s Little Mermaid and the latest remake of Cyrano de Bergerac now filming in Sicily.

He has not yet worked on a personal library for a work-from-homer keen to upgrade his or her backdrop for the next six months of video conferencing, but he’s open to the gig. “We’re pretty flexible, and I like a challenge.”

Anyone who can’t afford Foster, though, can opt for a budget alternative: Penguin Random House offers themed “credibility bookshelves”, free to download from its website. “Literary Heavyweight” features Zadie Smith and Ta-Nehisi Coates, while “Classics Collector” is heavy on Austen and Brontë. Hopefully, Gove and co have downloaded a few for their next appearance.

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