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You might remember women "getting their colours done" in the 1980s. Thanks to social media, the art of analysing which shades complement a person's natural colouring is again having a moment. Rachel Bilu of Colour Lab Stylist tells Susie Ferguson about the benefits.

A collection of letters written to and from iconic New Zealand painter Colin McCahon sheds light on a special relationship spanning four decades. McCahon met penpal Ron O'Reilly in 1938, when the pair were just 19 and 24 respectively. They wrote to each other regularly, amassing hundreds of letters covering McCahon's art practice, the contemporary art scene, ideas, philosophy, and spiritual life. A selection of the letters chosen by McCahon scholar Peter Simpson has been published in a new book Dear Colin, Dear Ron - with an afterword by McCahon's grandson Finn.

Thirty years ago, nurse Maybelle Ngapere McLeod realised a genetic link to the stomach cancer which killed many of her whanau was much more likely that the effect of a curse. She took her suspicions to Otago university, and the rest is history. Maybelle is part of the team awarded the top Prime Minister's Science Prize for transformative impact. The Hereditary Diffuse Gastric Cancer Team is led by Professor Parry Guilford, Director of the Centre for Translational Cancer Research at the University of Otago, in conjunction with members of the McLeod whanau and their community in Mount Maunganui. The research has resulted in a genetic test which gives the ability to understand their risk of cancer and take life-saving action. Professor Guilford joins Susie, along with Mabelle Ngapere McLeod and fellow team member, and whanau University of Otago Associate Professor Karyn Paringatai.

For those with asparagus patches: what to do to prep for a boomer crop in spring. Or, if you are planning an asparagus patch: how to kick start it.

Grace Blakeley takes aim at capitalism in her latest book Vulture Capitalism: Corporate Crimes, Backdoor Bailouts and the Death of Freedom. In the book, Blakeley asserts that rather than failing, capitalism is working exactly as intended - allowing corporate and political elites to advance their own interests at the expense of the rest of us. Susie is joined by Grace to discuss how instead of feeling powerless, there is a new path we can take to democratise the economy for a better future for all.

From the A303 in Wiltshire, motorists can catch sight of the megalithic structure of Stonehenge. But as a primary route for both commuters and holiday makers the road is notoriously traffic-clogged, and plans to upgrade the road have been decades in the making. However, the plans face strong opposition. They include building a road tunnel under the World Heritage Site in Wiltshire and costs have surged as high as £2.5 billion ($5.3 billion). John Adams is the chairman of the Stonehenge Alliance, a group dedicated to fighting the project that they consider too vast and intrusive to the prehistoric site.

It's thirty years since the 1994 genocide against the Tutsis in Rwanda, perpetrated by the Hutu-led government. British journalist Michela Wrong's book Do Not Disturb, The Story of a Political Murder and an African Regime Gone Bad explores the legacy of the genocide, exposing a murderous in-coming regime that operates on a "grand scale deceit", exercising a destabilising influence on the wider region. Michela has reported from and written about Africa for almost three decades, working for Reuters and the Financial Times. Michela is visiting NZ this week, giving a series of talks at the invitation of the New Zealand Institute of International Affairs.

The arrival of photography to New Zealand in 1848 was more about business than art. A cumbersome kit meant photographers needed carriages or horses to lug their gear across unsealed roads to sell their wares. These early images provide a valuable insight to the country's colonial era, with stunning portraits and landscapes now being presented in a new book entitled A Different Light: First Photographs of Aotearoa. Susie is joined by Shaun Higgins who, along with fellow book editor Catherine Hammond, has pulled together the extraordinary and extensive photographic collections of three major research libraries - Auckland Museum, Hocken Collections, and Alexander Turnbull Library. The book is also being celebrated with a travelling exhibition.

Former soldier Christian Lewis had hit rock bottom and was so severely depressed he would shut himself in his flat for weeks. But one day he made an impulsive decision, setting himself the challenge of walking the entire coastline of the UK. Christian joins Susie to talk about his new book, Finding Hildasay, which explores how with just ten pounds in his pocket and a few supplies, he walked himself into a brighter future.

New Zealand's volcanoes are world renowned, and most Kiwis are familiar with our big ones such as Ruapehu, Taranaki and Tarawera. But what about our lesser talked about volcanoes? GNS Science principal scientist Graham Leonard joins Susie to chat about some of the volcanic areas around the country that people are less familiar with - from Northland's periodically active field to volcanoes buried in the Canterbury plains gravels.