‘I didn’t kill her.’ Pauline’s voice was higher than normal. ‘Why would I kill her?’

‘Revenge. Money. Plenty of reasons I can think of.’ Palmer stroked his chin thoughtfully.

‘I’m in my mid-sixties, Detective. I have a bad hip. I am not a killer.’ She half laughed, finding the situation almost amusing.

‘How did you convince her to meet you on the common? Did you say you wanted to have a talk and work things out?’ Barrett asked.

‘This is absurd.’

‘A woman is dead. Murdered. I would say that absurd isn’t quite the right choice of word.’ Barrett spoke carefully.

‘I have told you, I went home after leaving the book club. I did not go to the common to meet her, or any such thing.’ Pauline was beginning to get irritated.

‘These are some messages sent between you and Toni. Do you recognise this conversation?’ Barrett slid the printed sheets across the table to her.

Pauline ran her eye over them and sighed. ‘Yes.’

‘It appears that you were threatening Toni Jones.’ Barrett sat back in his chair.

Pauline shrugged. ‘No comment.’

‘What do you think, sir?’ Back in the incident room, Palmer was eating a sandwich he’d grabbed when he went to see his son.

‘Well, we know she has motive.’ Barrett was standing looking at the board. ‘But she’s no killer. I can’t see her stripping the body and planting petals in the hair. It just doesn’t fit.’

‘I agree.’ Palmer brushed some crumbs off his trousers. ‘I’ve asked for the CCTV footage from Huntingdon Road, going in to Bar Hill, from six-thirty onwards. Perhaps that will confirm the time she returned home.’

‘Good work. Once you’ve been through the footage come and get me. I’ll be in my office.’

‘Sir, because of the way the body was treated, are you sure we shouldn’t start thinking it’s possible that this is a serial?’

‘No, not yet. Let’s investigate the facts, Joe, not some hunch.’ Barrett growled. ‘At the moment we have one body, one crime. Don’t get ahead of yourself.’

‘Yes, sir. I’ll get on to the CCTV right away. The sooner we prove where Pauline was, the better.’

Palmer sat down at his desk and turned on his computer. The screen flashed up telling him he had one new email and he was pleased to see it was from the traffic police. Palmer prepared himself for a very boring hour watching cars on the main road, keeping his eyes peeled for Pauline’s car, but after only five minutes he saw what he was looking for. The time on the recording was 6.37pm.

‘Bingo.’ Palmer leapt out of his seat and knocked on Barrett’s door.

‘Come in,’ Barrett boomed from inside.

‘It looks like we will need to release Pauline Robinson, sir. Her car was on Huntingdon Road at six thirty-seven. She couldn’t have killed Toni Jones.’