Summary. It was Xerxes, and the cause was a mistake he will carry to his grave — he took a lost, half-dressed stranger for a danger to Aziz, and broke his neck for it in the small hours; the burglary he and Lavinia swear to is a tale fixed between them by morning, and does not survive an unforced door.

The Reckoning. Zane died of a single blow, bare-handed, no weapon left and no struggle marked upon him — the manner of a man dispatching a threat and then going in to his rest, not a thief's death and not a duel. That plainness is itself telling. A staged intruder is usually dressed for the part, or the room shows some sign of a fight for the plate; here nothing was taken, no drawer disturbed, and every lock in the house sound come morning. A burglar who forces nothing and steals nothing is no burglar at all. The trail told the truer story: a stud dropped, a smear on a bannister, a rug rucked at the turning, running not from any outer door but inward, from the direction of Lavinia's own wing. The man had not broken in. He had been put out — hurried from a bed not his to be found in, shirt and coat left behind in his haste — and had lost himself in a dark house he did not know, wandering by ill chance into Aziz's room instead of the passage that would have returned him to the world. Xerxes, wakeful as ever, found a half-dressed stranger standing over his sleeping ward and did what he has always been ready to do for that boy: he ended the danger before it could show its shape. There was no danger. There was only a man who had taken a wrong turning in his shirtsleeves.

The herrings fall quickly. Lavinia was in her own wing when the blow was struck, and it is Xerxes, not she, who owns the act outright; her distress under questioning marks her as a woman propping up a story she did not do the deed to earn, not as a hand that broke a neck. Aziz slept through the whole of it and woke only at the noise — he neither found the man nor raised a hand against him. Wat was below-stairs on Xerxes's own errands, seen there by two of the staff across the death window, nowhere near the far wing. Gaunt was out the gate and refused readmittance before midnight, well clear of the hour and ignorant of any tryst to avenge. The Colonel had gone home to Cruikshank Manor after dinner, vouched by his own household, and held no quarrel with a footman he scarcely knew.

The motive, when it is finally said plainly, is a small and sorry thing: Xerxes killed to protect a boy from a peril that did not exist. Zane was no burglar and no seducer of Aziz — he was a man fled from an attachment in Lavinia's rooms of a kind the house did not speak of, caught wandering half-dressed in the wrong wing at the wrong hour, and killed for a danger that lived only in an anxious guardian's reckoning. Lavinia's part was only ever to keep the true shape of that night from coming out, and she has done it badly. I had near forgot the shirt — it was never found in Aziz's room nor in the passage between, only in Lavinia's own grate, half burnt. That, more than the trail or the tale, settles where the man had truly been. Xerxes will answer for the killing; the third this twelvemonth, by my count, and I do not expect it will be the last from this house.

When Xerxes heard a stranger in the hall,
He struck at Zane before the light could fall.
The intruder crept through passages of stone,
But found his neck was broken, still, alone.
We learn that swift protection often brings
The very ruin that the watchman stings.