Twenty years ago this week two physicists at the University of Manchester published a ground-breaking paper describing the extraordinary qualities of graphene.

The thinnest and strongest material known to exist – and better at carrying electricity than any metal – its discovery was hailed as revolutionary.

But two decades on, it doesn’t seem to have changed the world, or if it has, it is doing so very quietly.

So, what happened?

We go on the trail of graphene, meeting Nobel Prize winner and Godfather of Graphene Andrew Geim, and learning what it has – and hasn’t – done and what might be next...

Also this week, how to kill an asteroid and we talk the “other” COP with chief scientific adviser to the government, Dame Angela McLean.

Presenter: Victoria Gill Producers: Sophie Ormiston, Ella Hubber & Gerry Holt Editor: Martin Smith Production Co-ordinator: Jana Bennett-Holesworth 

BBC Inside Science is produced in partnership with the Open University.