Experience the most extraordinary ride in the universe – falling into a black hole.

The deepest hole humankind ever dug only got one thousandth of the way through the earth. But what would happen if you kept digging?

What would happen if there really was a lift that took you all the way up to space?

Find out why turning into a huge giant would be no fairy tale.

Experience the ultimate in long-distance travel - a holiday on Mars!

Good news - it’s possible to levitate! Bad news – there are some serious side effects.

Clouds might look like cotton wool, but if they were, things would get very messy.

Find out why stopping the Earth from spinning isn’t such a good idea.

Things don’t quite go to plan when the moon turns into cheese.

Find out why a flat Earth would feel very unflat indeed!

The planet is being destroyed - but this episode demonstrates the things you can do to help save it.

It really is possible to time travel into the future, and the team show you how!

If you have always wanted to shrink yourself, this is the episode for you!

Some day people will live on the moon – find out just what they are in for.

What if you could turn things to gold? This episode shows that it might not work out that well.

Want to reach for the stars? It would be the journey of a lifetime - literally.

Find out why living in slow motion would let you see things no-one else can!

Would it be possible to live on an Earth shaped like a doughnut? You might be surprised!

A fun run goes wrong when one ambitious runner tries running at the speed of sound.

What happens if you try to catch a falling star? Spoiler alert - probably best not to try!

Why waking up with lizard powers would make you useless on earth but a superhero in space!

It’s the ultimate baking challenge: making a gingerbread house you could actually live in.

Is it really possible to teleport? Spoiler alert: it could end in disaster!

Empty the oceans and you’d see hidden wonders, but you’d also cause the end of the world.

See what would happen if you really could switch off the sun.

Anyone can fly like a bird – you just have to travel across the solar system to do it!

Could you build a slide to the other side of the world? You would need to start in space, use the slippiest slide ever and make sure you have enough supplies before you go down it.

Wouldn't it be cool to be able to walk through walls? From turning into a gas to quantum trickery, we discover why it wouldn't be quite as useful as you'd like.

Bugs might be annoying, but we would soon regret it if we got rid of them - all our favourite foods would disappear, and there would be dung everywhere.

From cloning to 3D printing, what if we could actually make copies of ourselves?

Imagine if we had a thermostat that could turn the world temperature down - could we fix global warming? But be careful, a few degrees too far and could cause an ice age.

Venus has acid rain, crushing pressure and is hotter than an oven, so it might not sound like the ideal place to live. However, up in the clouds it's almost just like home.

Find out how to shout from one side of the world to the other.

We try out three potential ways to become invisible and discover some surprising side effects.

There is a way that Earth could have a second sun, so we try it out to see what happens.

We imagine a world where it's possible to move things with your mind like films, but find that the laws of physics mean that this superpower wouldn't quite work like you expect.

We look at whether some animals can get gigantic and find out that if you are being chased by a giant snail or a humungous butterfly, then fear not, you must be dreaming.

We try using a gravity-bending black hole and spinning the earth faster to see if we can make it possible to walk on the ceiling.

What would the planet be like if all other humans disappeared, leaving you as the last person on earth?

Is it possible to build a sand castle the size of a real castle? We imagine how it could be done, using a pneumatic drill and a huge, solid gold steamroller.

We find out what would happen if you shrank the earth. You could jump higher and move faster, but you would end up with altitude sickness even at sea level.

If you had a tree that could grow money, would that make you rich? Even if you wait 20 years for your tree to grow, you will probably end up no richer than you started.

Flying like a superhero may sound like enormous fun, but there are some serious downsides that Hollywood does not tell you about - weather, extreme cold and even fizzy blood.

Imagine removing all the colours one by one? It would change more than just how things look, and after taking out just three colours, we would not be able to see anything at all.

If everyone in the world ate nothing but cheeseburgers, we would run out of land, and even if we went meat-free, we would have to invent some crazy burgers to get the nutrients we need.

To throw a ball around the world, you need to start out in space, throw it ten times the speed of a bullet and make sure your ball does not explode when it hits the atmosphere.

We reveal how to create the ultimate in tall buildings by going to the moon and taking inspiration from wedding cakes.

To win a marathon, are you better off with the bouncing legs of a kangaroo, the long legs of a T. rex or sticking with the legs of a human?

We imagine becoming unbreakable by removing our bones, turning our skin to metal and finally by becoming completely elastic, but indestructibility isn't everything we hoped for.

Sometimes you want to go surfing, but it's too far to the beach, so we try surfing on land with the help of a volcano and some giant fans.

We try out a crazy idea from science fiction to build a giant sphere around the sun and give us more energy than we'll ever need.

We take inspiration from the natural world as we imagine a new kind of superhero that can walk up walls.