Swallow caught the slightest wink from Pat Mossop’s eye. The little Belfast man notoriously hated pomposity and condescension. Swallow’s invocation of his own rank had clearly improved the monsignor’s manners.

They followed the priest, moving out through the mourners to cross Rathmines Road. It was dark now and cold, with evening setting in.

The parochial house was generously illuminated with gas lights in the hallway and in the front rooms. The interior smelled of food and beeswax polish. Feehan showed them to a large, comfortably furnished parlour on the ground floor. He sat first and then gestured them to straight chairs around a solid oak table. A coal fire burned in the grate, making the room pleasantly warm.

‘You may remove your overcoats if you wish,’ Feehan said. It was something between an invitation and an instruction.

‘Thank you, no,’ Swallow answered. ‘We won’t detain you any longer than we have to.’

If Feehan picked up Swallow’s implicit assertion of his authority, he let it pass.

‘This is a shocking thing,’ he said slowly, his expression solemn. ‘Within yards of this church, the house of God. A very pious young woman from a good-living family. What do you think can have happened?’

Pat Mossop opened his notebook on table and sat, his pencil poised. The monsignor’s eyes registered displeasure. ‘Is your sergeant taking notes of what I am saying, Mr Swallow?’ The tone was hostile again now. ‘I am under no obligation to speak to you. The law of the Church is above the law of man. And you should understand that I am personally known to the new superintendent at Rathmines, Mr Boyle. A fine, upstanding Catholic gentleman, if I may say so.’

‘Absolutely,’ Swallow said. ‘Superintendent Boyle is all of those things. But this is standard procedure, Monsignor.’

Mossop grimaced. ‘That’s correct, sir. Any detail may be important in a serious case like this, and has to be committed to paper. That’s my job. I’m sure that if Superintendent Boyle were here he’d confirm that to you.’

Before Feehan could respond, the door opened without a knock. A tall young priest with neatly parted blond hair, perhaps in his late twenties, looked into the room. ‘Pardon me, Monsignor,’ he said, glancing at Swallow and Mossop. ‘I heard you had visitors. Is there anything the housekeeper can get you before she finishes up? Some tea perhaps?’

Feehan waved a hand. ‘Thank you, no, Father Cavendish. That won’t be necessary.’ He made no pretence of introducing the two G-men or offering them refreshment.

‘How well did you know the dead girl, Monsignor?’ Swallow asked when the young priest had left.

‘It would be more correct to say that I know the family rather than . . . the deceased. They are poor people, as you can see, but decent, hard-working and loyal to their faith. The sort of family our church is built on, gentlemen.’