In this mind-bending series, Professor Jim Al-Khalili explores the vast range of size in the universe, from tiny atoms to gigantic, interconnected galaxies.
In the first episode, Jim will enter the world of objects that are too tiny to glimpse with the naked eye. Starting with the smallest insects, he moves on to encounter living cells with amazing superpowers and confronts some of humanity's deadliest enemies in the form of viruses. Going smaller still, he encounters wondrous new nanomaterials such as graphene, discovered by physicist Andre Geim. These are revolutionising engineering, medicine, computing, electronics and environmental science. Finally, Jim comes face to face with the fundamental building blocks of the world around us – atoms – and reveals why understanding the science of the 'small' is crucial to the future of humanity.

Cosmic rays capable of destroying human DNA are hurtling through outer space like subatomic bullets, causing space crews radiation damage.
Cosmic rays are intergalactic alien interlopers on our Milky Way. But the source of their power is a mystery. Are they coming from other galaxies? Are they coming from things in between the galaxies? Where do cosmic rays come from? Truth is, the most powerful ones, we haven't got a clue. The race is on to solve the mystery of the fastest particles in the universe.

There's evidence that dark matter makes up 85% of all the matter in the universe. We can see dark matter holding galaxies together and ripping other structures apart, we even see it bending light. Dark matter itself has been around since the beginning of the universe. Without dark matter, we wouldn't be here. But if you can't see dark matter and if you can't touch it, does it really exist?
Dark Matter is thought to be the cosmic glue that holds the universe together, yet the search for it continues to eluded scientists today.