Mullen shook his head. ‘No, the kids didn’t have anything like that. They were more into PlayStations and video games. Well, Luanne had her baby toys, too. But wooden dinosaurs? No.’

‘So where did it come from?’

‘I couldn’t tell you.’ He looked at the photos again. ‘Where would you buy this kind of thing?’

‘Who else might be in the habit of buying toys for your children?’

‘Their grandparents, of course. Or my brother-in-law, John. He and Lindsay saw a lot of each other – John might have picked the thing up somewhere, I suppose.’

Fry put the photos back in the file. The toy wasn’t important, really. Many fathers would be vague about what their children played with.

‘Let’s leave that for a moment then, sir. Just walk this way, would you? And mind where you tread. Stick to the stepping plates.’

Offering up a small piece of information seemed to have given Mullen confidence. At least he was doing something positive.

‘What do you want me to see now?’

‘The hallway, sir. The hallway is important. Although the fire started in the sitting room, it was the smoke filling the hallway and rising up the stairs that caused the real problem.’

‘I know about this. I tried to get into the house, if you remember. The smoke was so bad that I couldn’t see anything, or even breathe.’

‘Quite right. If the firefighters hadn’t pulled you back, you might well have been more seriously injured.’

‘So what do you want to know?’

‘I was wondering who left the door open from the sitting room into the hall. That was what provided enough air for the fire to get a hold. It was also what allowed the smoke to spread through the rest of the house. If the fire had been contained in the sitting room a bit longer, the alarm might have been raised soon enough for lives to be saved.’

Mullen said nothing, but stood gazing at the stairs. Behind him, his family liaison officer appeared, grimacing at Fry. But she took no notice.

‘Were the doors downstairs normally left closed at night, Mr Mullen?’

‘Which doors?’

‘From the sitting room to the kitchen, for example?’

‘Yes.’

‘And what about this door, the one into the hall?’

‘Well, maybe. But Lindsay might have left that one open. She sometimes did, if I was out. She knew I’d close it when I came home and went to bed. Only I didn’t . . .’

‘I know. I’m sorry if this distresses you, sir. Just one last thing. Were you aware of anyone hanging around near the house in the days before the fire? Did any of the neighbours mention someone asking questions about you and your family?’

‘No, nothing like that.’

Fry nodded at the liaison officer, who came forward and put an arm round Mullen’s shoulders.

‘I tested the smoke alarm every month,’ said Mullen, with some difficulty.