Ellini let Robin sleep off the booze – or whatever it was that had made him so feverish – and picked up the thread of her furious thoughts right where she had left off in the slop house. 

She would go after the Wylies. She would save any other young men who'd had their feelings stolen by those bitter, manipulative women. And, in this way, she would avoid becoming a bitter, manipulative woman herself.

Robin understood her motivation better, though. And the next day, while they were walking through the Lambeth Public Baths, he voiced it with admirable succinctness.

"So you're going to get your revenge on men by offering them the humiliation of being saved by a woman?"

He had been inquisitive when he'd woken up, even if he was hung-over. There was no more talk about the people he'd killed, or the agony of remorse – in fact, she got the feeling he regretted saying as much as he had last night. But there had been plenty of questions.

With bleary eyes and a gravelly voice, he asked her where Jack was – "Oxford" – and why he wasn't here right now – "He thinks I'm dead."

Ellini delivered these explanations in a terse, haughty manner, trying to make it clear that she didn't intend to trust him, and she didn't believe in his so-called repentance, no matter how many notches he carved into his flesh. He hadn't carved anything onto his pretty face, had he? That was proof positive that he was still Robin.

She had to tell him a little bit about the Wylies – although she suspected, from the guarded look on his face, that he'd heard of them before. She didn't mention Myrrha's name, but she could tell he knew she was at the heart of it. Ellini wondered for a moment why she was trusting him to help her bring down the evil empire of his own wife, but there wasn't time to answer that question. She wouldn't get the answer for over a month.

Robin accepted her explanations without comment – although perhaps there were a few eyebrow-raises, particularly around the phrase 'He thinks I'm dead'. Then he took her to the Lambeth Public Baths.

For the last six months of the year, the Lambeth Baths were drained and turned into a gymnasium for men. It contained all sorts of equipment: dumb-bells, parallel bars, vaulting horses, a boxing-ring. In the echoey, tile-lined interior, dozens of men, wearing nothing but their vests and drawers, lifted dumb-bells, got each other in head-locks, practised fencing and counted push-ups.

The poster outside the baths-turned-gymnasium said it offered all kinds of 'healthful, manly exercise', and this was the reason why Robin had insisted she tie her hair up under a cap and put on men's clothing.

"Women aren't allowed in the gymnasia," he explained, as they walked through the raised gallery – what would have been the side of the pool in warmer weather. "It would be impossible for you to dress modestly and still use the equipment. And anyway, all that vigorous exercise can damage your childbearing capability. I met a Doctor once in Berne who said that women's organs can go rattling about inside their torsos if they're not careful. Your organs need support at all times. That's why you have to wear a corset."

"Really?" said Ellini, watching as one of the men below her vaulted the horse, the contents of his long-johns flapping under the thin cotton. "It's your organs that look vulnerable to me."

Robin grinned. "I don't know what happened to you in Oxford, but I like it."

She didn't rise to this. Instead, she pulled warily at the waistcoat he had given her to put on, and said, "Where did you get these clothes?"

"You know how women will do anything for me?" This wasn't a boast but a long-established fact, and Ellini acknowledged it with a stony-faced nod. "Well, some men will do anything for me too. The boy who gave me those clothes was as pretty as you."

Ellini didn't like the past tense. "You didn't-?"

"Oh no," said Robin, waving a hand. "I could understand if you were sceptical, but I really don't do that anymore. I'm supposed to be meeting him for a drink later, but I think I won't turn up. When you've arranged to meet someone like me for a drink, the nicest thing that can happen to you is that I don't turn up."

He said the last part with so much bitterness that Ellini didn't have the heart to say anything, even though she completely agreed with him.

She didn't know if Robin liked men as much as he liked women, but they certainly liked him. His pretty, feline face had always made him very popular with both sexes. He thought nothing of using this popularity to get what he wanted – he probably still thought nothing of it, because it was so much milder than his murderous rampages that it seemed more like a charming foible than a vice.

"It was unnecessary really," he went on. "I do have money. The Dowager Duchess of Portsmouth left me an annuity when she died, although it's possible the bank clerks might be confused when I come to collect it, since I'm supposed to be dead too."

Ellini stared at him. "If you have money then why were you living like a vagrant on the docks last night?"

"There was no reason not to. But, if you're serious about this revenge campaign, I'll rent us some rooms in Lambeth Palace Road, and we'll-"

She shook her head in exasperation. Her time in the slop-house had left her tetchy about wasted money. "That's twice as expensive as anywhere else in the district."

"You've never played the revenge game before, have you, Ellie? It requires style. We'll pose as a doctor and his wife-"

"Excuse me, we will pose as a doctor and his sister."

Robin chuckled. He was enjoying this far too much. "Blind as I usually am to it, Ellie, the fact that we're of different races might give the game away there. Besides, there are too many questions if you're my sister. Why aren't you married? How did I get lumbered with you? A doctor's wife can disappear, even if she's pretty, but a doctor's sister will always be the object of speculation. Don't worry, I'll make sure we have separate bedrooms."

"Oh? And that won't provoke questions?"

"Of course not. Plenty of men can't stand their wives. Anyway, I'll be mostly in my study-"

"An apartment on Lambeth Palace Road with a study?" said Ellini, throwing up her hands in despair. "How much is this annuity? What did you do for this Duchess?"

Robin waved a dismissive hand. "That's a story I wouldn't dream of burdening my young wife with. Let's got back to this revenge scheme of yours."

"I really don't understand why you keep calling it that."

"When I was last conjured down to that academic-woman's study, they told me Jack had forgotten you. Is he one of the men who's fallen victim to the Wylies? And, if so, are you going to save him too?"

"He's already been saved," said Ellini – although, angry as she was, she hesitated to use the word 'saved' for what she'd done to him.

"You mean he remembers you now?" said Robin slowly. "And he thinks you're dead?" There was a short silence, and then an appreciative laugh. "Oh god, that's brilliant! He'll go insane!"

He thought about it for a moment, and then muttered, "I suppose we would have read about it in the papers if he'd killed himself..."

"He's not going to kill himself, and he's not going to go insane," said Ellini briskly. "He doesn't give a damn about me."

This time, it was Robin who was silent, as though he, too, was wondering how much information to divulge. 

In the end, he plunged his hands into his pockets and said, "Of course, it's very characteristic of you, Ellie, to go after the people who are exploiting these men, rather than the men themselves. Out-and-out revenge would be too crude for you. But you must know that most men would rather die than owe their life to a woman – especially a young, pretty woman – and, in the circumstances you're describing, I'm not sure that saving them would be doing them a favour. What good would it do to give them back their feelings and memories? If they haven't driven their loved ones to suicide, they've probably treated them like dirt. How can love come back there? How can they get over what they did?"

"Well, this is a question you can answer from your own experience, more or less," said Ellini. "Would you rather have stayed dead, never realizing what you'd done, or how your victims suffered? Or are you glad you know the truth now, even if you can't do anything to make it right? Isn't that why you carved those notches into your chest? Isn't it some measure of atonement that you know, and that you suffer?"

Robin gave her a grimacing look from out of the corner of his eye. "That's very characteristic of you too. What if I were to tell you that it does no practical good for anyone to suffer, if suffering is the only end in mind?"

"I disagree. I think that, through suffering, we learn to be better people."

"The opposite is almost always the case." He sighed. "I suppose I'm glad I know. I suppose Jack's glad he knows," he added, giving her another shrewd, sideways glance. "It offers the slimmest, tiniest chance of redemption."

Ellini said nothing. She didn't see that either he or Jack deserved anything of the kind.

But it seemed that Robin didn't want to think about redemption either, because he gestured down at the furious activity beneath them. "Now, why do you think I've brought you here?"

"I assumed we were going to use the boxing-ring," said Ellini. "Perhaps after-hours, when my untethered female organs won't cause a scandal."

"You're partly right," said Robin, smiling again at her acid tongue. "I do intend that we should use this place after-hours, but not just the boxing-ring. I've been thinking a lot about the challenge of teaching you to fight, and I think the answer is to play to your strengths. You're small and not very strong. I could have you lifting dumb-bells and eating red meat until you're blue in the face, but nothing would change that. So, for you, grappling and wrestling is out of the question. But you're fast and agile, and you have an extraordinary talent for dodging and disappearing, so I think we should focus on that."

"You want to make me an Artful Dodger?" said Ellini.

But Robin was too swept up in his plans to pay her any attention. "We'll use the trapeze and the parallel bars – I'm even planning a trip to the circus – and I'll show you how to dodge blows and dance out of reach until just the right moment. Even then, I think we'll stick with brass knuckles and kicks to the face. You wouldn't want to kill."

"Do you really think I wouldn't want to kill, or do you just not want to teach me?"

Robin looked at her. "Both," he said, in an injured tone. "I know you."

He went on talking about the techniques he would teach her, the exercises they'd perform, with a boyish enthusiasm that reminded her painfully of Jack. She even felt the wound in her chest prickle, and tried to drag her thoughts away for fear that she would soon start bleeding through her shirt and drawing attention to herself.

She realized that Robin, for all his initial reluctance to teach her to fight, had now seized on the idea like a lifeline, and was using it to distract himself from his remorse. She still wasn't entirely sure she believed in his remorse, but he had thrown himself into this new challenge with a vigour that certainly suggested he was running from something.