Hey You What If?
Hey You What If? is a comedy program on CBBC. We answer the ‘what if’ questions that you never even thought to ask! Each episode asks a question and takes you on an unforgettable journey where the impossible is made possible to find the answer! The program has been available since 2025. A total of 34 episodes have been broadcast, most recently in January 2026.
Last episode
Hey You What If?
The deepest hole humankind ever dug only got one thousandth of the way through the earth. But what would happen if you kept digging?
Catching up on Hey You What If??
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Experience the most extraordinary ride in the universe – falling into a black hole.
It really is possible to time travel into the future, and the team show you how!
Series 2
Is it possible to build a sandcastle the size of a real castle? We imagine how it could be done, using a pneumatic drill and a huge, solid gold steamroller!
Series 1
Good news - it’s possible to levitate! Bad news – there are some serious side effects.
Series 2
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.
From cloning to 3D printing, what if we could actually make copies of ourselves?
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!
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.
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!
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.
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 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.
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 reveal how to create the ultimate in tall buildings by going to the moon and taking inspiration from wedding cakes.
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.
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.
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!
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.
Series 1, Episode 3 - You Could Take a Lift to Space?
Expected on
What would happen if there really was a lift that took you all the way up to space?