In 2010, the Yorkshire village of Melsonby was left in disbelief when postmistress Diana Garbutt was found murdered in the post office she ran with her husband, Robin. Robin claimed she'd been the victim of a violent intruder, but as detectives probed further, suspicion began to fall on him.

Prosecutors claimed  that behind the façade of a happy marriage lay deep marital and financial turmoil and £16,000 missing from the safe. They argued that when Diana confronted Robin over the missing money, he killed her. In 2011, Robin Garbutt was sentenced to life in prison.

Robin has always maintained his innocence and over the last 14 years has unsuccessfully appealed his conviction three times. But with one of the central planks of the prosecution coming from the Horizon system — the technology now at the centre of the Post Office scandal — Robin and his legal team are once again attempting to clear his name.

Murder at the Post Office meticulously re-examines the case, featuring voices on both sides: those convinced Robin was wrongfully convicted and others who are unsure and still suspect he is guilty.