What is the universe actually made of? Particle physicist Theresa Fruth join us at Shirtloads to explore one of science's greatest unsolved mysteries - dark matter! Making up roughly 85% of the universe, yet appearing in none of our known particles, dark matter is invisible, elusive and almost certainly the reason the universe (and us!) exist at all.

Theresa and her team are hunting for it anyway. Working 1.2 kilometres underground in a converted gold mine in regional Victoria, they're searching for WIMPs - weakly interacting massive particles - in one of the quietest, most interference-free environments on Earth. The lab is being built out now, and further experiments are on the horizon. We may be closer to one of the biggest discoveries in scientific history than we realise.