Imagine being able to travel back and forth in time – like the Doctor in her TARDIS, only for real, not in a television studio with fancy computer graphics.
It’s a pretty mind-blowing concept but time travel isn’t actually impossible, according to the laws of nature.
This Horizon documentary meets the scientists at the cutting edge of their field, including Professor Ronald Mallett, pictured above, who are continually making progress towards learning how it might be possible to travel through time.
It’s all about building wormholes, fully functioning time crystals and manipulating entangled photons (of course) which will let an engineer of the future make sci-fi a reality.
TV Times rating: ***