Miriam turned off the electrostatic barrier and the alarms, then deactivated the steel shutters that surrounded the bed itself if danger threatened. Her theory was that hiding was a far less effective deterrent than fortification. Before electronics Miriam had kept a kennel of killer dogs.

She dressed quickly, unlocked the bedroom door, and looked out. Dawn filled the upper parts of the house with golden light. She was beginning to feel hunger again, but she had no time for it now. She wished that she was already with Sarah. Without Miriam’s help the woman would go mad, unable to satisfy her own hunger, unable to stand the agony.

Once the transfusion was completed the body reacted in a predictable way. Before the advent of modern medical techniques the transfusion was a slow process, subject to the collapse of veins and infection from the crude apparatus available. Now it could all be done at once.

The physical effects would devastate Sarah’s body, but the psychological impact, as a new set of needs and instincts replaced her established human ways, would be catastrophic.

Miriam had nursed many of them through the agony of it and she intended to do the same for Sarah.

It would mean returning to their hospital, possibly to danger. They might try to capture her, even to kill her. If she was not very careful indeed she was likely to become their prisoner once she went back to Riverside. They would have ample justification to commit her, and the legal machinery was certainly available.

She could picture herself starving in agony as they prodded and sampled and tested. The trouble was, you didn’t die. You just got weaker and weaker until you ended up like the ones in the chests.

It took months to starve. King Charles IV of France had walled up twenty of her kind in a sewer where they were hiding in May of 1325. It was November before the last muffled wail was heard in the streets above. And even after that, they suffered.

She was clammy, trembling. For the first time in many years she was genuinely terrified. It had always been hard to do this, and Sarah Roberts was proving to be especially difficult.

But worth it. Well worth it.

She descended the steps. There was no time to call a limousine. She would have to break one of her rules of safety and take a taxi. Moving through her house, she checked the rooms for damaged belongings. John had left things alone, it seemed.