WALK INTO THE SUNNY, Kennington office of the woman who’s been called the most powerful person in British publishing, and of course the first thing you do is look at the bookshelves. They are crowded, though also decorated with mugs, treasures and family photographs that give the room a homely feel.

I tilt my head to read the names: Carl Hiassen, Salley Vickers, Francis King (Francis King!) . . . But Amanda Ross, the joint managing director of Cactus TV and the woman who brought the Richard & Judy Book Club into existence, is almost dismissive of the “most powerful” tag that has been attached to her.

“I really, really don’t — and I don’t pretend that I know what definitely will make a bestseller. That’s not how I choose the books. My criteria, honestly, is: is this book going to entertain and engage people enough to generate 12 to 15 minutes of gripping television? The bottom line is: what’s the sofa chat?” Ross’s influence is undeniable. The Richard & Judy Book Club has been going for three years on Channel 4; three years in which the ten books chosen to be discussed over ten weeks have gained increases in sales that most authors only dream of. Next week the club’s Summer Reads — six more titles, revealed exclusively below — will get a huge boost when viewers pack them for the beach along with the factor 15. A heavy book buyer, Ross points out, buys about 12 books a year. But a Richard & Judy viewer might buy 16 books . . . no wonder the sales figures look as they do.

I like Amanda Ross, her enthusiasm, her energy; there isn’t a jaded bone in her body. I’ve read that she talks about books only in sales terms, rather than discussing “literary merit”; that her views of the importance of story are simplistic.

Wrong. This is a woman who loves books, who clearly wants as many people as possible to share the enjoyment. She is an evangelist with the passion of the convert. “Books have always been a kind of exotic thing for me because I grew up in a house without any books. My family is very working-class, so we had some kind of children’s encyclopaedia, a medical dictionary, and that was about it. My mum joined a book club for me and I used to get things like Black Beauty, Heidi, which I used to devour completely.

“But books weren’t part of my family culture at all. At university — I was the first person in my family to go to university — I remember doing Knots, by R. D. Laing, and being completely gobsmacked that several people’s parents had it at home. So I was very jealous of these people, and it’s always been my ambition to have my own library, and to have my own house absolutely full of books. I don’t throw books away, I can’t; to me they are special, lovely things.”

All this sounds breezy, a bit too easy, I think: what’s the sofa chat? But isn’t that the question that applies to any reader, any book? Every reader wants to engage with books; that means thinking about them, talking about them. “What’s the sofa chat?” is as good a way as any as expressing this. She refers, more than once, to a book having “good take-away”; nothing to do with KFC, but whether the reader will get something lasting from the book; Nicole Krauss’s The History of Love, I’d say, has stellar takeaway; so does Julian Barnes’s Arthur & George. Both were Richard & Judy choices this year.

Ross read drama at Birmingham; Cactus TV was set up in 1994 with her husband, Simon Ross (brother of Jonathan). The company signed Richard Madeley and Judy Finnigan in 2001 and today the show averages 2.2 million viewers. The Richard & Judy Book Club — which she conceived and insisted upon as a part of the show — runs for ten weeks, culminating in the British Book Awards, which is broadcast on Channel 4.

Why just ten weeks? “The danger in telly is that if something is successful people repeat it endlessly; but you can’t do a book club all year round. You can’t buy a book a week, year round.” In the first year the club’s choice of Star of the Sea, by Joseph O’Connor (who until then had been graced with plenty of critical praise but no significant sales), caught everyone’s attention. The week before its appearance on Richard & Judy the book sold four and a half thousand copies; sales jumped by eight thousand copies the week it was featured, and rose steadily.

This year sales of Kate Mosse’s Labyrinth have overshadowed everything else on the list. Mosse has nothing but praise for Ross, and as a founder of the Orange Prize and presenter of Readers and Writers Roadshow, on BBC Four, as well as being the author of novels and nonfiction books, she knows what she’s talking about. “Amanda is such a high-powered executive, but she’s also excellent at knowing what it feels like to be an author. I got a handwritten, detailed letter from her about Labyrinth, and a beautiful timepiece — it was such a lovely gesture.”

Ross makes sure that when the author’s section is filmed for the show — Mosse’s, for instance, on location in Carcassone — the whole crew, everyone, reads the book first. “The reason she has succeeded in making books work on television is that she is a passionate reader who cares about books and authors,” Mosse says.

Ross has the final say on all the book club choices, although a team of four looks at them. By the time they get down to the last ten, it’s all a question of balance. (And not just of tone; you can’t ask people to read too many fat books, she says — the list always goes “thick thin, thick thin”.) She reveals that this year Jonathan Safran Foer’s Extremely Loud and Incredibly Close made it to the last 20; he’s married to Nicole Krauss, and there was some discussion of what would happen if a husband and wife appeared on the show. In the event, though, Foer didn’t make it.

Julian Barnes’s Man Booker shortlisted Arthur & George wasn’t submitted by the publisher; Ross called it in because she’d heard how great it was. (It’s reassuring to learn that publishing’s miraculous elixir, word-of-mouth, can play a part in her choices.) “Critics who don’t watch the show have preconceptions about what the author’s attitude is going to be,” she says. “I read some rubbishy stuff that people said when I chose Julian Barnes — they thought that he wouldn’t like to be in the book club. But he loved it! Pat Kavanagh — his wife, who also happens to be his agent — said that for the first time he hadn’t found it too painful to see himself on TV. But we do check, when books are suggested, that publishers don’t submit anyone who isn’t going to be committed to the whole process: they have to come to the Book Awards. Either you buy into it, or you don’t.”

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