Brian Cox and Robin Ince are joined by actor and writer Mark Gatiss, theoretical physicists Carlo Rovelli and Fay Dowker to ask timely questions about time. Is time real, does it exist in the fundamental laws of physics, and if it doesn't, why do we experience the sensation of time passing? They look at the idea of the block universe, where our future is as real as our past, which worryingly leads to Robin's favourite question about free will...is that an illusion too? A timely look at the question of time and hopefully just in time... Producer: Alexandra Feachem