In his introduction to Joy in the Morning, the ninth of the so-called Jeeves books, PG Wodehouse wonders aloud for how long it might be considered decent to continue writing about the adventures of the same set of characters. At around the same point in the lifespan of the Ross O'Carroll-Kelly series, I asked myself the same question. Having followed the course of the former Castlerock College captain's life through nine novels, I inevitably wondered, what next? What I hadn't foreseen was that the arc of Ross's story – like the fortunes of so many others – was about to turn on a steeply downward trajectory.

I began writing The Oh My God Delusion in the early days of 2009, when the Irish economy was unravelling at a pace that was truly dizzying.

That, looking back, was the most difficult job I had in writing the book: how do you produce a modern satire about real events when the reality is so unbelievable as to be almost beyond parody?

Brian Lenihan was wrong when he said that we all partied during the years of the Celtic Tiger but there was undeniably a shift in material values in Ireland during that period.

One of my least fond memories of it is how difficult it was to carry out a simple transaction in the bank without being asked by a teller what your 'plans' were for the money in your savings account. Having been brought up to believe in the principle that money was something you worked for, not the other way around, my own plan was that the bank might put my money into a big safe and perhaps still have it when I came looking for it in a year or two. Of course that was considered crazy talk.

The Oh My God Delusion is, I hope, a comeuppance story – the original working title was 'The Bonfire of the Inanities' – as gravity claims its forfeit from Ross and all the modern-day Icaruses in his circle.

His wife Sorcha's boutique is in financial straits. His mother, a celebrity chef on daytime television, has been ordered by RTÉ to start cooking meals that better reflect the current economic paradigm. And his estate agent friend JP is forced to reinvent himself as a repo man.

While I was writing the book, I read all four of John Updike's Rabbit Angstrom novels, which might account for the darker-than-normal tone of some of the passages. But I think it might be the funniest of the 10 Ross novels I've written. It's certainly the most topical and definitely the one I'll look back on with most pride.

The Oh My God Delusion by Ross O'Carroll-Kelly, published by Penguin, is the Sunday Tribune Book Club's choice for January

Winner of December's choice

We've chosen Niall Burke from Glounthaune, Co Cork as our best reviewer of December's choice, One Day by David Nicholls. He wrote: "A UK publishing sensation soon to go global with a forthcoming film adaption due in 2011, One Day uses a clever conceit of returning to the two main characters on the same day, 15 July, over 20 years. One can't help being enthralled by the lives of Emma and Dexter as we see them mature from early 20s studenthood to responsible (or irresponsible) middle age, attacking each chapter with a voyeuristic fervour to discover the latest twists in their lives, loves and careers. Absorbing, smart, highly readable and highly recommended."

Competition

The Sunday Tribune Book Club's monthly book choice is announced in the latter half of each month. Readers are invited to submit their book reviews, totalling no more than 100 words, by email to bookclub@tribune.ie or via our Facebook and Twitter pages. Every month, we'll publish the best review and the winner will receive a €100 book token courtesy of National Book Tokens. (See nationalbooktokens.ie for more.) So get reading... and reviewing!