A former book publicist at Random House in New York, Sloane Crosley is the author of two bestselling essay collections, I Was Told There’d Be Cake and How Did You Get This Number, and has been described as the Dorothy Parker of the 21st century. The Clasp, her hectic and funny first novel, comes with high praise from, among others, Michael Chabon and David Sedaris. Inspired by Guy de Maupassant’s story, The Necklace, it is about three college friends – Kezia, who works for a crazed jewellery designer; Nathaniel, who is trying and failing to make it in Hollywood; and Victor, now unemployed, having been fired by the search engine for which he did something in “data” – who embark on the trail of a legendary but long-lost piece of jewellery…

Is it more nerve-racking publishing a novel than your personal essays?
Yes. Everyone assumes that nonfiction is the more exposing. But I don’t feel like that. With nonfiction, you’re bouncing off facts. At a certain point, you’ll hit a wall, and on that wall will be written: “I was nine”, or “this is just the way it happened”, or whatever. The nature of fiction, though, is that you must make so many decisions. You have to think about every ice cube in every glass of whisky.

Your last book came out in 2010. How long did The Clasp take you to write?
When How Did You Get This Number came out, I was still at Random House. I finally left at the start of 2011, and began work on it full-time. I’m extremely motivated by fear. A lot of people do that thing – which is admirable, but not me – where they tell no one they’re working on a novel, and then it just sort of appears. Very cool. I’m not that cool. When I left my job, the New York Times ran a piece about me, and I said then I’d be working on a novel. I thought: if I tell the Times, then I have to do it.

Were you writing with the fans of your essays in mind?
Well, my second book was darker than my first – I was at an odd place in my life; it had a break-up essay in it, me wandering lonely through Lisbon – and some people didn’t like it as much. So The Clasp feels like a return to my first book, in terms of its humour. Plus, you have more room in a novel. The sadness can be woven through it. But it’s not a book about eight generations of Iraqi women. I don’t have the chops to do that.

It’s based on a story by de Maupassant. Why that story in particular?
I wanted to write a novel that was a tribute to the short story – I’m a short-story fiend – and The Necklace, which is essentially a fable, is an easy hook on which to hang your hat: its characters’ motivations are very modern. But I didn’t want to follow it too closely; I just wanted to hit the narrative with little de Maupassant-shaped arrows. It’s a caper. I wanted to get my characters on a plane, and to go in search of treasure. The world doesn’t need another book about people moping around in Brooklyn, and I wanted to be Indiana Jones once upon a time, so I did that part for myself.

Two of your characters are (convincing) men. Were they difficult to write?
For the minutiae, I consulted male friends. You know: are they thinking about their genitals enough? That kind of thing. But of course, that’s a trap. It’s too simplistic. That’s why men who write women always describe their clothes endlessly. I can’t remember what I wore yesterday, can you? I know men like Victor, who are always on the edge of the group, and I liked crawling into Nathaniel’s mind [he is lecherous, and convinced of his charm]. I’ve dated a guy like that… or seven. It was important to me to have male characters, and a woman character who isn’t at all like me. I’d spent a decade writing books in which “I” was the most common vowel. I didn’t want there to be any confusion.

What do you make of the seemingly growing demand among readers for characters to be “likable”?
It’s ridiculous. If characters are to be realistic, they can’t always be likable. Canadian Elle asked me why my characters are sometimes mean to each other. I thought: this is such a Canadian question. [Laughs] But I would turn it around. Perhaps it’s the mirror they don’t like. I would aim the accusation back at readers. If you find someone so dislikable, what is it that is really bothering you? Have they got under your skin? Have you seen something of yourself in them? Have they betrayed you?

Do you miss your old job? Was it impossible to be publicist and writer?
Yes, I miss it. I’m a relatively rare bird, in that I’m quite a social writer, and I loved my job. It takes time to get used to it, that thing – Victor experiences it in the book – when you only know it’s raining because your mail is damp. But I couldn’t have continued to do both. It was becoming awkward. Before I left, I was on a book tour. I’d taken my vacation at the same time, but it was, well, a very public vacation, and one of my authors thought I wasn’t looking out for his book. That said, 19 out of 22 of them were supportive. I don’t think Alice Munro, Dave Eggers and Joan Didion were going to get a chip on their shoulders because of anything I did.

Will you read your reviews?
Yes, and no. I’ll read the New York Times. I felt like it was strange when my authors said they didn’t read theirs. I’m not immune to criticism but I spent a lot of time advising other people how to take it. One trick with Amazon reviews – I spot-check them sometimes – is to click on the reviewer’s name and see what else they’ve written about. [Laughs] All right, so Jean’s last purchase was a Swiffer [a brand of mop]! You have to be tough to a degree. It’s weird when people ask: are you still writing? I don’t say to them: are you still a dentist or did you give that hobby up? But I also like to keep in mind something I heard Jim Crace say, which is that the writer is a volunteer, there to entertain. I mean, if the world ends, and there on a desert island is a doctor, a nurse, an engineer and you, who gets eaten first? The writer! He’s been sitting round all day. He’s nice and plump.

What will you do next?
I’m working on some more essays. But the trick is going to be keeping myself sane through this process, which may prove a bit impossible.

The Clasp is published by Random House (£12.99). Click here to buy it for £10.39