It's appropriate that Kevin Bloom, Richard Poplak and I are at The Radium beerhall in Johannesburg to talk about the pair's long-awaited book Continental Shift. Subtitled A Journey into Africa's Changing Fortunes, the book, as anyone who knows the two authors can tell you, has taken a long time to get here.Many of the conversations that led Bloom and Poplak to spend five years travelling to 18 countries on the continent took place here, in one of Johannesburg's oldest bars. Those conversations were sparked by a trip nine years ago to Rundu, an old defence force base in Namibia, on the Angolan border.As Bloom recalls, "We were hanging with ex-SADF mercenaries who had just stuck around and they were telling us stories about what was going on on the other side of the river and they said we could get across without any passport hassles.so we went to the other side and hung around in southern Angola for a while in a town called Calai."What they found there was a town whose population had increased fourfold since the end of Angola's civil war. A hotel had just been built, local schools were back up and running, and the lights were on after many years of darkness.The changes in fortune of a town far from the oil riches of the capital, Luanda, were "the pre-emptive spark that allowed us to start having a series of conversations about what development meant, what growth meant, whether growth led to development, what was happening on the continent, and whether [what had happened in Calai] was a more comprehensive phenomenon or was isolated to this one town," said Poplak.The two Johannesburg Jewish boykies were born three months apart around the corner from each other and have been best friends for decades. In the time since their trip to Rundu they've both published books about their experiences of Johannesburg and pursued careers as journalists. For readers familiar with their personal narrative voices and sometimes gonzo stylings, Continental Shift presents a surprisingly data-filled, historically detailed exploration of the circumstances of each of the countries it examines - a noticeable departure in tone. The 10 essays that make up the book can be read as stand-alones but they also work together as an attempt to do justice to a series of big questions about where the continent finds itself in the 21st century.Its long gestation is a sign of the ways in which the authors' preconceptions have been shifted by their experiences.Bloom admits that "we had a shitload of fun. It was amazing. Not many boys get to do this with your best mate from childhood. It was incredible and, the more countries we did, the less drunk we got, the more we listened, the more we took in what was around us and the more we soaked it in."But there were times when it seemed that finding a way to tell the story would elude them.At first the book was envisioned as an exploration of Chinese involvement in post-colonial African development but when that proved impossible the idea of a single theme was abandoned.Both writers remember the day in August 2013 when, as Poplak tells it, they realised "that we needed to dial-down our voices massively and start dealing exclusively with what was in the notebooks. It wasn't necessarily a logical decision when you think about travel writing because that always involves massive wads of subjectivity with the 'I' voice used as a filter. We tried that and it sucked."Once the decision was made to go back to the drawing board, Bloom said, and although "800000 polished words and a lot of countries hit the floor", they finally "knew the questions and from there it just flowed. We were going to look at the middle class in Namibia, Chinese infrastructure in Botswana, the failed state in Zimbabwe, Nollywood in Nigeria, resources in the DRC, agriculture in Ethiopia, the first country in south Sudan and civil war within a Francophone context in the Central African Republic. Once we set about starting to deal with the questions, we weren't that concerned with the answers. We were concerned about doing justice to the questions."The wrestling and wait were worth it and the book is a world-class piece of investigative journalism that gives a complex picture of a diverse continent the constituents of which are too often lumped under convenient one-size-fits-all slogans that do more harm than good.For South Africans it's also a book that will open your eyes to both the similarities and differences between us and the rest of Africa.Far too often we are arrogant about, and dismissive of, the continent and, for Bloom, "Africa exposes South Africa's self-deceit time and time again".It's to be hoped that the book will go some way to changing that.Continental Shift, by Kevin Bloom and Richard Poplak, published by Jonathan Ball, R265..