Andrew Patrick held the weapon – which turned out to be an imitation – at Alistair Rankine before giving him a bag he said contained a bomb.
Patrick – who pretended to be Polish – then ordered the cabbie to steal cash from a Bank of Scotland branch in Kirkcaldy, Fife.
Mr Rankine handed over a note to staff which said they had only minutes to fill the bag and that bombs would explode if police were called. The letter also claimed he had a bomb strapped to his body.
But when Mr Rankine eventually left the bank with almost £10,000, Patrick had made off.
Armed police and an army bomb unit soon arrived. The explosives were also found to be fake, consisting of little more than tubes, cotton wool and a phone circuit board.
Patrick was later caught following a media appeal. The 40-year-old yesterday admitted assault and robbery and will be sentenced next month.
The first offender had been working at the time as an instructor at the Fitness Factor gym in Kirkcaldy. He was earning up to £300 a week, but prosecutor Allan Nicol said it appeared he had faced “some financial difficulties”.
Mr Rankine was working at around 1pm on 11 November last year when he was asked to make a pick-up at an industrial estate in Lochgelly, Fife.
It was Patrick, using a fake accent, who had made the call to the taxi office.
When Mr Rankine arrived, Patrick got into the cab while clutching two holdalls. He was also wearing a cap, sunglasses and had his chin covered with a scarf. He gave directions but they ended up at a dead-end in Kirkcaldy. Patrick pulled out a handgun and said: “You’ll be safe if you do what I say.”
He handed a note to Mr Rankine and insisted he hand it to staff at the Bank of Scotland in the town’s Carberry Road. Anxious staff initially filled the bag with around £7,000, but Mr Rankine said “they would not be happy with that” and asked for more.
Mr Rankine continues to suffer flashbacks, insomnia, anxiety and fear. Lord Bannatyne remanded Patrick, of Lochgelly, in custody.