‘You must answer counsel’s question, Miss Potter. Are you ready to continue? We really must get on.’ As ever his Lordship was all heart.

‘What did he ask me?’

‘I want to know why you identified Mr Gallagher, the accused, in court?’

‘I was told to.’

The answer was barely audible to most people in the court. Muirhead heard it and exploded with his response.

‘What! What did you just say?’ Muirhead had not been sure what to expect, but he certainly had not expected this.

‘I was threatened.’

‘By whom?’

‘I told you, I don’t know. The man with the Irish accent, Bob, came to my flat. I didn’t know I’d been with Kevin Boyle till the police spoke to me. I realised I’d been set up. This man told me that when I came to court, I was to pick out the accused and say that I saw him in the pub on the night I was paid to sleep with this guy Mike. The bit about him being a poof is true. I didn’t know it was Kevin Boyle. He gave me a photograph and told me where I could meet Mike. If I didn’t point out Mr Gallagher, he would come back and cut me. He had a knife with him and he drew it down my face. He wasn’t joking. I was scared. I’m still scared. I didn’t know what to do.’

‘When did this happen?’

‘Last night. He told me not to tell anyone.’

‘The man in court – have you ever seen him before in your life?’

‘No. I’m sorry. I’m so sorry.’

Muirhead returned slowly and deliberately to his seat and sat down.

‘Great stuff. One to the bad guys, methinks!’

Muirhead nodded his appreciation to his junior.

The Advocate Depute prolonged her torment and re-examined for the better part of an hour, but the girl would not budge. Yes, she had lied but now she was telling the truth.

The first day of the case came to an end with the defence unscathed. Indeed, the fact that a crucial prosecution witness had been discredited meant that, with luck, the defence was a goal up in the minds of the jury. However, there was still a long way to go.

As the court prepared to adjourn, a lone figure slipped out of the public gallery and hurried down the stairs.

Muirhead was driving home, reflecting on the day’s events. When he came out of court it took his mind some time to slow down. He would go over and over the day’s evidence trying to assess its impact, where it fitted into the scheme of things, checking in case anything had been overlooked.

So far, so good. The dock identification had been a considerable shock, especially so early in the trial. He knew he had taken a gamble, but it had paid handsome dividends. However, he could do without more surprises like that. There was still some very difficult evidence waiting in the wings.