Catch up TV
Series 1: 25. You Could Switch Off the Sun?
See what would happen if you really could switch off the sun.
Source: CBBC
Most recent episodes of Hey You What If?
Hey You What If?
Series 1: 1. You Fell Into A Black Hole?
Experience the most extraordinary ride in the universe – falling into a black hole.
21-07-2026
CBBC
Hey You What If?
Series 1: 16. You Could Actually Reach For The Stars?
Want to reach for the stars? It would be the journey of a lifetime - literally.
19-06-2026
CBBC
Hey You What If?
Series 1: 15. Everything You Touched Turned To Gold?
What if you could turn things to gold? This episode shows that it might not work out that well.
18-06-2026
CBBC
Hey You What If?
Series 1: 14. You Could Live On The Moon?
Some day people will live on the moon – find out just what they are in for.
17-06-2026
CBBC
Hey You What If?
Series 1: 13. You Could Shrink Yourself?
If you have always wanted to shrink yourself, this is the episode for you!
16-06-2026
CBBC
Hey You What If?
Series 1: 12. You Can't Wait For Christmas?
It really is possible to time travel into the future, and the team show you how!
15-06-2026
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.
22-05-2026
CBBC
Hey You What If?
Series 1: 10. The Earth Was Flat?
Find out why a flat earth would feel very unflat indeed!
21-05-2026
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.
20-05-2026
CBBC
Hey You What If?
Series 1: 8. The Earth Stopped Spinning?
Find out why stopping the earth from spinning isn’t such a good idea.
19-05-2026
CBBC
Most popular episodes of Hey You What If?
Hey You What If?
Series 1: 6. You Could Levitate?
Good news - it’s possible to levitate! Bad news – there are some serious side effects.
15-05-2026
CBBC
Hey You What If?
Series 2: 22. You Had Kangaroo Legs
Running a marathon is hard. At least it is for a human. But what if we could swap our legs with an animal – would that make it any easier? \n\nFirst, we try ...
29-04-2026
CBBC
Hey You What If?
Series 1: 21. You Woke Up As A Lizard Superhero?
Why waking up with lizard powers would make you useless on earth but a superhero in space!
02-03-2026
CBBC
Hey You What If?
Series 1: 5. You Could Go On Holiday To Mars?
Experience the ultimate in long-distance travel - a holiday on Mars!
14-05-2026
CBBC
Hey You What If?
Series 2: 17. You Flew Like A Superhero
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.
22-04-2026
CBBC
Hey You What If?
Series 1: 19. You Could Run At The Speed Of Sound?
A fun run goes wrong when one ambitious runner tries running at the speed of sound.
10-03-2026
CBBC
Hey You What If?
Series 1: 8. The Earth Stopped Spinning?
Find out why stopping the earth from spinning isn’t such a good idea.
19-05-2026
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.
20-04-2026
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.
20-05-2026
CBBC
Hey You What If?
Series 2: 19. You Only Ate Burgers
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 ...
24-04-2026
CBBC