Horizon journeys into the human memory, from how it emerges in childhood, develops through to adulthood, and fades in middle age. You might think that your memory is there to help you remember facts, such as birthdays or shopping lists. If so, you would be very wrong. The ability to travel back in time in your mind is, perhaps, your most remarkable ability, and develops over your lifespan. Horizon takes viewers on an extraordinary journey into the human memory. From the woman who is having her most traumatic memories wiped by a pill, to the man with no memory, this film reveals how these remarkable human stories are transforming our understanding of this unique human ability. The findings reveal the startling truth that everyone is little more than their own memory.