There are almost a million people in the UK living with dementia, and Alzheimer’s is the most common form. But the disease actually starts long before any noticeable symptoms appear, and over the past decade, studies have shown that it is much more complex than previously thought. Julie Williams has been at the forefront of this effort, uncovering the genes that make us susceptible, and has transformed our understanding of this devastating disease. She has brought researchers together to create bigger datasets and more powerful studies. Her current work with scientists from other fields, like immunology and computational biology, is looking at the mechanisms underlying Alzheimer’s disease. Julie tells Jim about her early interest in science, her time as Chief Scientific Advisor to the Welsh government, and her belief in ‘team science’ – collaborating and sharing research findings across international borders and disciplines. Produced by Florian Bohr

Since 1900, our best estimates suggest that earthquakes have caused around 2.3 million deaths worldwide; we saw the devastating effects of one just recently, in Turkey and Syria. And as scientists have been at pains to point out over the years, there is no reliable short-term warning system. But thanks to the work of people like James Jackson, an Emeritus Professor of Active Tectonics at the University of Cambridge, we are finding new ways of understanding and withstanding seismic activity. James tells Jim Al-Khalili about his career travelling the world in search of quake sites and fault lines – trialling new technology and techniques in a quest to understand the processes that shake and shape our planet’s surface; and working out how this information can help vulnerable cities become more resilient to quakes in future... Produced by Lucy Taylor.

Marie Johnston is a pioneer in the field of health psychology: the discipline that seeks to understand how psychological, behavioural and cultural factors contribute to our physical and mental health. Today an emeritus professor in health psychology at the University of Aberdeen, her career exploring behavioural interventions has shown that even the subtlest shift in how we act can dramatically change our behaviour and lives for the better – whether that’s in an individual recovering from a stroke, or a nation coming to terms with pandemic safety measures, while her work setting up the UK’s first stress management clinic showed why mental health support needed to come out of psychiatric hospitals and into general practice. Marie tells Professor Jim Al-Khalili why she believes the right interventions can be a powerful tool in improving public health, and indeed our healthcare system; and how an accident at the hairdresser's many years ago helped her become more approachable... Produced by Lucy Taylor.

Professor Dame Julia King, Baroness Brown of Cambridge, is an engineer whose fascination with metals, and skill for handling both research projects and people, has taken her from academia to industry to the House of Lords. She tells Jim Al-Khalili how the dressmaking skills she learnt from her mother as a child helped her to understand the composite structures used in wind turbines later in life. And how she designed metal alloys that are resistant to both large and small cracks. As the author of the UK government's Review of Low Carbon Cars in 2007, Julia set out a route to decarbonising a major segment of the transport sector within 25 years, making an important contribution to the UK's plans to try and achieve Net Zero. But achieving Net Zero is not enough. With demand for electricity set to double or treble by 2050, there’s an urgent need to radically reform our national infrastructure and guarantee supply. Julia became a cross-bench member of the House of Lords in 2015. She’s now chair of its Science and Technology Committee, holding the government to account on its promise to make the UK a science superpower.

Jim Al-Khalili talks T cells, our immune response and Long Covid with Prof Danny Altmann. Danny Altmann joined ‘team T cells’ in his twenties and has been studying how these killer operate ever since. How do they know which cells to search and destroy? The T cell wing of our immune response is highly targeted and incredibly clever, on a par with the most sophisticated military intelligence operation and in recent decades there have been dramatic advances in our understanding of how it all works . Danny tells Jim how he came to study our immune response to all sorts of pathogens, from anthrax to zika, why he spends every morning from 5 to 6am in the bath reading 19th century classics and why he’s determined to try and understand Long Covid. Producer: Anna Buckley

Jim Al-Khalili talks to astrophysicist Haley Gomez about defying expectations and becoming a world expert on cosmic dust. For centuries, cosmic dust was a major source of irritation to optical astronomers because, like smog, it stopped them from seeing the stars. Now studies of these tiny particles are challenging some deeply held assumptions about the physics of the universe. Haley’s research has changed the textbook explanation of how cosmic dust is formed and helped to open our eyes to just how many galaxies there are in the universe. In 2018 she was awarded an MBE for services to physics and inspiring the next generation of physicists and astronomers from less privileged communities. A cause which is very close to her heart. Produced by Anna Buckley and recorded in the Pier Head Building in Cardiff as part of the Cardiff Science Festival.

How a once-derided approach to statistics paved the way for AI. Jim Al-Khalili talks to pioneering mathematician, Professor Sir Adrian Smith. Accused early in his career of ‘trying to destroy the processes of science’, Adrian went on to prove that a branch of statistics (invented by the Reverend Thomas Bayes in 1764) could be used by computers to analyse vast sets of data and to learn from that data. His mathematical proofs showed that Bayesian statistics could be applied to all sorts of real world problems: from improving survival rates for kidney transplant patients to tracking Russian submarines. And paved the way for a dramatic explosion in machine learning and AI. Working as a civil servant (2008-2012) he helped to protect the science budget in 2010, transforming the landscape for scientific research in the UK. And he has been vocal, over many years, about the urgent need to make sure children in the UK leave school more mathematically able. In 2020, he became President of the UK's prestigious national science academy, The Royal Society. Producer: Anna Buckley

Clifford Johnson's career to date has spanned some seemingly very different industries - from exploring quantum mechanics around string theory and black holes, to consulting on some of Hollywood's biggest movies; but it makes sense once you understand his ambition of making science accessible to all. A Professor in the Department of Physics and Astronomy at the University of Southern California in Los Angeles, Clifford's worked in the United States for decades – but was born in the UK, then spent his formative years on the Caribbean island of Montserrat, before moving back to England to study. Here, he fell in love with quantum mechanics - before moving to the US, where he's broken new ground in finding ways to talk about quantum gravity and black holes. Clifford's other big passion is getting as many people as possible engaged with science, making it more exciting, entertaining and most importantly diverse - and it's this attitude that's led to regular work as a science consultant on various TV shows and films; and even a recent cameo in a major movie... Produced by Lucy Taylor.

A fur-stripped mouse carcase might not sound like the cosiest of homes – but that’s where the burying beetle makes its nest; and where Rebecca Kilner has focused much of her research. A Professor of Evolutionary Biology at the University of Cambridge, Rebecca’s work – initially with cuckoos, then more recently with the beetles – has shed invaluable light on the relationship between social behaviours and evolution. She tells Jim Al-Khalili how the beetles’ helpfully swift generational churn and mouse-based parenting has allowed her team to study evolution in action, demonstrating for the first time what was previously just evolutionary theory. Producer: Lucy Taylor

Motor Neuron Disease (MND) is a degenerative disease that relentlessly attacks the human nervous system, deteriorating muscle function to the point where patients can no longer move, talk, eat, or even breathe. To date there’s no cure, and until fairly recently there were only minimal treatments to ease the symptoms. Pam Shaw has dedicated her career to changing that. A Professor of Neurology at Sheffield University and Founding Director of the Sheffield Institute for Translational Neuroscience, she recently led clinical trials into a drug that delivered unprecedented results: showing that it could slow the progression of MND in certain patients, and even improve symptoms for some. It’s just one small step – but with a new tranche of research funding and a national institute to study the disease on the cards, Pamela believes this could be the start of real progress in understanding and treating Motor Neuron Disease. Producer: Lucy Taylor