The government’s principal civil servant for Ireland, Chief Secretary Sir Arthur Balfour, and his wife would be attending a luncheon at the Royal Dublin Society at Ballsbridge. The ultra-loyal RDS was the least likely location for trouble, but since the murders five years previously in the Phoenix Park of the chief secretary’s predecessor in office, Sir Frederick Cavendish, along with his under-secretary, no chances could be taken. The protection detail would require the presence in concealment of two armed detectives and a sergeant.

Three G-men were engaged in watching the movements of two Irish-American gentlemen staying at the Imperial Hotel. The word from a helpful porter was that they were former Union Army officers with guns to sell. So far their principal focus appeared to be on drinking whiskey and making passes at the barmaids, but they had left word with the porter that they were expecting visitors. G-men would be required to take shifts sitting in the hotel bar, watching for someone to make a rendezvous.

Swallow also needed two men to operate the public office and the cells at Exchange Court. That should leave him with a paltry strength of three or four to cope with whatever the crime reports might bring in.

The moment he stepped into Exchange Court he knew from the face of the young G-man at the public counter that things were not good.

‘Bad story out in the E, sir.’ He jerked his head towards the stairs. ‘Sergeant Mossop’s above. He’s just ahead of you.’ Pat Mossop had been duty sergeant for the night shift that had just ended. Swallow took the stairs to the crime office two at a time.

Mossop, recently promoted to detective sergeant, was hunched at his desk. Detective Johnny Vizzard, newly arrived in G-Division on promotion from uniform, was perched beside him, his fingers poised over the typewriter. Mossop looked tired, as he always did now. A year ago the diminutive Belfast man had taken a bullet in the upper torso as G-men closed on an armed suspect on Ormond Quay. Strictly speaking, Pat Mossop should have been dead. Had his colleagues not got him swiftly to the infirmary on Jervis Street, he would have been.

‘Something big, Pat?’

‘Big enough, boss. E-district. Rathmines Road. A bad assault. Could be more than that. I thought I’d have the report done before you came in.’

‘Tell me.’

‘I’m just back with the lads from the Baggot Street Hospital. A young girl was attacked in Blackberry Lane off the Rathmines Road some time towards midnight. She’s in a bad state. The doctor says she mightn’t come through it.’

‘How much do we know?’