The Ropers sprang a surprise. They had, after all, been very much awake, for a crash in the kitchen had aroused them. And at this Mrs Arbuthnot’s hand flew to her throat and she gave a little choking gasp. “The bread bin!” she said. “I knocked it from the shelf.”
“Ah.” Appleby turned to the man Roper, a quiet, wary fellow with the ability to stand absolutely still. “And, once aroused, will you tell us what you heard, either from this room or from any other room in the apartment?”
“We heard three people talking in here: Mr and Mrs Arbuthnot and the dead man, Mr Slade.”
“It’s a lie!” Arbuthnot had sprung to his feet.
And his wife too sprang up, quivering. “How dare you,” she gasped, facing the servants. “How dare you tell such a wicked untruth.”
But Roper merely looked very grim. “There’s no lie in it,” he said quietly. “It’s true we both quickly fell asleep again, perhaps before the murder happened. But your three voices we can swear to. So it is Mr Arbuthnot who is lying when he says he never left his bed.”
There was a silence. Appleby turned to Mrs Roper, a pale, nervous woman who was softly wringing her hands. “You have heard what your husband has just said. Do you corroborate it in every detail?”
Mrs Roper nodded. “Yes,” she said. “Yes, it’s true – God help them.”
“Do you know anything that you believe it would be useful to add?”
But Mrs Roper shook her head. “No, sir. There isn’t anything more.”
Arbuthnot was now pale to the lips. “There were three voices,” he said hoarsely. “But not mine. I didn’t stir.”
Suddenly Mrs Arbuthnot gave a shrill, hysterical laugh and turned to her husband. “George,” she said, “it’s no good. They heard you. My fibs about burglars and diamonds are useless. There’s nothing for it but to confess that you came out of the bedroom and – and quarrelled with Rupert as you did.” Again she laughed wildly. “You had reason enough, God knows. And I will admit it – admit it openly in court. Perhaps that will save you.”
Arbuthnot was staring at his wife with dilated eyes. “For God’s sake–” he began.
But the Sergeant closed upon him. “George Arbuthnot, I arrest you on the charge of the wilful murder of Rupert Slade. And it is my duty to warn you–”
Appleby, who had been making a quick tour of the room, intervened. “No,” he said. “Mr Arbuthnot is entirely innocent. It was his wife who killed Slade.”