Catch up TV
Series 2: 3. We Got Rid of Bugs
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!
Source: CBBC
Most recent episodes of Hey You What If?
Hey You What If?
Series 2: 5. You Could Stop Global Warming
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 could cause an ice age.
09-05-2025
CBBC
Hey You What If?
Series 2: 4. You Needed Two Of You
From cloning to 3D printing, what if we could actually make copies of ourselves?
08-05-2025
CBBC
Hey You What If?
Series 2: 3. We Got Rid Of Bugs
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!
07-05-2025
CBBC
Hey You What If?
Series 2: 2. You Walked Through Walls
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.
06-05-2025
CBBC
Hey You What If?
Series 2: 1. You Built A Mega Slide
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!
05-05-2025
CBBC
Hey You What If?
Series 2: 9. We Had Two Suns
There is a way that Earth could have a second sun, so we try it out to see what happens.
14-03-2025
CBBC
Hey You What If?
Series 2: 15. You Shrunk The Earth
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.
13-03-2025
CBBC
Hey You What If?
Series 2: 10. Your Mind Could Move Things
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'd expect.
12-03-2025
CBBC
Hey You What If?
Series 2: 20. You Threw A Ball Round The World
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.
11-03-2025
CBBC
Hey You What If?
Series 1: 9. The Moon Was Made Of Cheese?
Things don’t quite go to plan when the moon turns into cheese.
31-01-2025
CBBC
Most popular episodes of Hey You What If?
Hey You What If?
Series 2: 18. There Were No Colours
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!
04-10-2024
CBBC
Hey You What If?
Series 1: 2. You Could Dig Through The Earth?
The deepest hole humankind ever dug only got one thousandth of the way through the earth. But what would happen if you kept digging?
18-12-2024
CBBC
Hey You What If?
Series 2: 1. You Built A Mega Slide
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!
05-05-2025
CBBC
Hey You What If?
Series 2: 15. You Shrunk The Earth
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.
13-03-2025
CBBC
Hey You What If?
Series 2: 13. You Were The Last Person On Earth
What would the planet be like if all other humans disappeared, leaving you as the last person on earth?
06-10-2024
CBBC
Hey You What If?
Series 2: 11. Animals Were Supersized
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.
22-09-2024
CBBC
Hey You What If?
Series 2: 26. You Could Walk Up Walls
We take inspiration from the natural world as we imagine a new kind of superhero that can walk up walls.
15-03-2024
CBBC
Hey You What If?
Series 1: 25. You Could Switch Off The Sun?
See what would happen if you really could switch off the sun.
13-06-2022
CBBC
Hey You What If?
Series 1: 11. We Could Actually Stop Climate Change?
The planet is being destroyed - but this episode demonstrates the things you can do to help save it.
24-10-2023
CBBC
Hey You What If?
Series 2: 14. You Built A Giant Sandcastle
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!
30-08-2024
CBBC