Roald Dahl Day is celebrated each year on 13 September. Dahl gave us much-loved children’s books like Matilda, The BFG and Charlie and the Chocolate Factory, which have captivated kids for generations.

Dahl is also a controversial figure, and made anti-semitic remarks that his family have since apologised for. We explore the separation of art and artist, and go looking for the science hidden in Dahl’s fantastical stories.

We find out about the scientists brewing up chocolate – not in a factory, but in a laboratory. And remember how the BFG sent ‘golden dreams’ into kids’ bedrooms? We hear how anaesthetists are ensuring that patients enjoy good dreams while sedated. And remember Bruce Bogtrotter, the much-loved side character in Matilda who famously scoffed a gigantic chocolate cake? Inspired by his story, we decided to chew over the science behind eating competitions with Professor James Smoliga from Tufts University School of Medicine.

Presenter: Marnie Chesterton, Tristan Ahtone and Sandy Ong

The 80th birthday celebrations of the late, great Queen frontman Freddie Mercury have us marvelling at mercury at an elemental level: as a killer, a cure and more.

First, we hear about how to make a telescope mirror out of a spinning bowl of liquid mercury. Then we hear about killer queens; it’s a gruesome tale of pheromone-induced ant warfare.

Next, Freddie’s rare condition that caused him to have four extra incisors in his upper jaw leads us to discuss the secrets hidden within our teeth. We’re joined by archaeologist Carolyn Freiwald from the University of Mississippi, whose work on the teeth of ancient people tells us much about both their lives and our own.

Also, the secret to getting rid of earworms, ancient civilisations hidden beneath the Amazon, and why you should never mess with dimethyl mercury.

Presenter: Marnie Chesterton, Kai Kupferschmidt and Camilla Mota

Vast swathes of Europe and Asia are experiencing drought conditions, thanks to relentless heatwaves and lack of rain.

This week, we find out why drought conditions could unexpectedly lead to an increase in water-borne disease.

Next up, we take a trip to Lake Malawi to discover why a tiny fly could help us rewrite the science of insects.

Also on the show, we’re joined by Professor Dan Parsons from Loughborough University in the UK, who tells us about the rivers that lurk beneath the sea.

Elsewhere, we hear about the tech that could help reduce textile waste, we find out why rehydrating raisins won’t turn them back into grapes, and discover how to suck water from thin air.

All that, plus many more Unexpected Elements.

Presenter: Marnie Chesterton, with Chhavi Sachdev and Phillys Mwatee

News of an Australian library book finally finding its way home 150 years after it was borrowed has the Unexpected Elements team thinking about things that get forgotten, filed away or simply turn up much later than expected.

We start with the story of a meteorite from Mars that spent millions of years travelling through space before ending up in a university drawer. Then, we investigate why scientists believe California may be centuries overdue for a massive earthquake known as "The Big One".

Next, Martin Woodward from GitHub joins us to explain how millions of lines of computer code are being preserved deep beneath the Arctic in a vault designed to protect humanity's digital knowledge for generations to come.

Plus, we hear about the penguin vaccinators working to protect Australian wildlife from bird flu, discover if smells, tastes and touch can be measured, and explore the dying art of reading a book.

Presenter: Marnie Chesterton

As Europe experiences its first total solar eclipse in almost 30 years this week, Unexpected Elements investigates the surprising science that emerges when sunlight is blocked out.

We travel to the forests of Italy, where we investigate whether trees can communicate their eclipse plans to each other. We learn about an ambitious scientific plan to launch a wall of bubbles the size of Brazil into outer space. And we contemplate whether astronauts will ever need to take rice cookers the moon.

Also on the show, Anneliese Hodge, a doctoral researcher from the University of Plymouth in the UK joins us to help us learn more about how sunscreen - while good for us humans - can be destructive to marine life.

Elsewhere in the programme, we hear about the newly arrived crows bothering the people of Nairobi, Kenya, and discuss another pesky problem: people not wearing headphones on public transport.

All that plus more unexpected elements.

Presenter: Alex Lathbridge

Producers: Dan Welsh, Lucy Davies and Robbie Wojciechowski

The UK's Royal Society for the Protection of Birds has found that birdwatching is the second-fastest growing hobby amongst Gen Z with 750,000 of them regularly venturing into the outdoors to spot some of our feathered friends. Inspired by this new appreciation for an old pastime, the Unexpected Elements team are on the lookout for some birdwatching science.

First, we watch birds, but did you know they watch us back? We hear how crows don't just hold grudges; they also pass on those grudges to their peers. Then, from birds watching us to birds watching for us. We learn all about the patterns of vulture crime scene detectives.

Inspired by the citizen science nature of bird watching we talk to Professor Brooke Simmons about Galaxy Zoo, a website where people can volunteer to sort through images of galaxies and perhaps stumble on some mysterious green blobs.

We also bring you the newest evidence of ice age-old bird appreciation, explore BALLS or the ambitious pan-African experiment to send spherical radio antennae to the moon, and ask does music distract or help you concentrate? The answer might depend on your social skills.

All that plus more unexpected elements.

Presenter: Marnie Chesterton

Producers: Ella Hubber, Lucy Davies and Robbie Wojciechowski

75 years ago, Walt Disney's Alice in Wonderland hit our screens, welcoming us into a technicolour, topsy-turvy world of eccentric characters – including the Mad Hatter, the Cheshire Cat, the Queen of Hearts, the White Rabbit and many more.

On Unexpected Elements, we're tumbling down the rabbit hole to uncover the strange and surprising science hidden within the classic story.

We’ll find out how bizzarro land of Lewis Carroll's original novel was inspired by the real scientific discoveries of his time? Dr. Franziska Kohlt tells us how Wonderland made sense of science for children – and we learn about a few scientific theories that have taken inspiration from Alice herself.

We also meet shrinking shrews, get wide-eyed over some adorable animals, and go underground to solve a subatomic puzzle.

All that, plus many more Unexpected Elements.

Presenter: Marnie Chesterton

If you were lucky enough to be at rapper Pitbull's recent concert in Hyde Park in London, you would have been greeted by a sea of bald caps. A Guiness World record-breaking sea of 22,141 bald caps. And, in honour of this incredible feat, the Unexpected Elements team are exploring some science.

First, is hair the secret to healing? We find out why trading fur for sweat may have had unexpected consequences. Then, we learn all about ball lightning – real life fireballs that, despite first being sighted over 800 years ago, remain a mystery.

Next, is your garden full of rap stars? We're joined by Elizabeth MacDougall-Shackleton who tells us what we can learn from sparrows' surprisingly aggressive rap battles. We're also joined by Paulo Bittencourt who proves why we should all appreciate a nice big tree.

All that, plus many more Unexpected Elements.

Presenter: Marnie Chesterton

As the film adaptation of the Odyssey bursts onto screens around the world this week, here at Unexpected Elements we’re undertaking our own epic journey through science – all inspired by the ancient Greek epic.

First, we discover the tiny virus that’s using its own Trojan Horse to sneak into cells it wouldn’t usually be able to infect. Then, we hear about the daring 8000km voyage undertaken by iguanas 30 million years ago.

Next, we’re joined by Professor Steve Simpson from the University of Bristol in the UK. He tells us how he’s been using sounds to lure fish back to coral reefs around the world – much like how the Sirens in the Odyssey used their enticing songs to lure sailors to shore. Except in Steve’s work, rather than being lured to their deaths, the fish are helping corals recover from the devastating effects of climate change.

Also, the fake medicine that still makes you feel better and why some smells might make you sleepy.

All that, plus many more Unexpected Elements.

Presenter: Marnie Chesterton, with Emmanuel Samani and Chhavi Sachdev

A mysterious vigilante in Mexico nicknamed “Batman” has inspired the Unexpected Elements team to investigate the science of superheroes.

First up, we explore whether a Batman’s presence can actually change human behaviour. One unusual psychology experiment suggests that people may be more likely to perform acts of kindness when a caped crusader appears nearby.

Then we discover a real human superpower: echolocation. Used by bats and many other animals, it turns out humans can learn to navigate the world using sound as well.

Next, we meet Mexico’s original Bat Man, conservationist Dr Rodrigo Medellín. He joins us to bust myths about a much maligned mammal, reveal how one species helps make tequila possible, and confess to keeping vampire bats in his bathroom.

Plus, how environmental DNA is helping researchers map biodiversity across the Arctic Ocean and a reflection on scientific heroes. Are great discoveries are ever really the work of just one person?

All that, plus many more Unexpected Elements.

Presenter: Caroline Steel, with Meral Jamal and Phillys Mwatee