‘Good,’ I said. ‘But be careful, be discreet. I know it’s odd but I want you to go in a minute – get a sandwich somewhere, not here, and go back to the office. I’ll go out first and sit back where I was. You come out then and walk past me, as if you don’t know me, pretend you were just at the loo. Now – I need to get one of the exhibits out of the box and I’ll take all the documents you prepared. When you get back to the office, lock the box back in my drawer immediately. Do it before you eat your lunch. Please. I’ll explain everything later.’

‘It’s like fecking Tinker Tailor Soldier Spy, Finn,’ Tina said.

I couldn’t smile. I had to tell her about Rhona before she heard it elsewhere.

Five minutes after Tina had gone, I got up, paid for my un-drunk tea and left the pub. I crossed Oliver Plunkett Street to the GPO. Once inside, I walked at speed to the far door, exited on to Pembroke Street and crossed the narrow street to Mayne’s. The seats at the end of the bar, just inside the front door, were free. I ordered an Americano, left €2.50 on the counter, and sat in the second seat out from the wall. I could see whoever came in and went out. But, more importantly, I had space to deal with the package Tina had given me. I took the bagged coaster exhibit and labelled it with the sticky labels Tina had brought ‘DC1’. Next, I labelled the items that I had got from Ann with ‘DC2’ and ‘DC3’.

I tugged some of my own hair out by the root, put it in a bag, and labelled it ‘FF1’. Waiting for Tina in the Long Valley, I had realised that I had to submit a sample, in case Deirdre’s hair and toothbrushes didn’t yield enough DNA to extract a reading. As a fallback, my own DNA – that of a sister or a half-sister – could identify Deirdre’s. I would find out if we had the same father by default after all.

I had the pen that I had given Gill to use bagged up already. I labelled it ‘JG1’. Then, I used a clip to attach all five exhibits to the covering letter Tina had typed for me, and signed the covering letter and my credit card payment authorisation. Finally, I put everything into the A4 padded envelope, pre-addressed by Tina to Setanta Forensic Laboratories, and sealed it. I fitted the envelope back into my handbag and wound the long strap around my wrist a couple of times. For all my precautions, it was impossible to tell if I had been followed into the pub. After all, I didn’t know who I was looking for.