She padded quietly after the little group, allowing them to move along four paces ahead of her. They passed the lavatory. They passed the refreshment room. In his total confidence the Hawk didn’t bother to look back. With a display of a jolly young uncle’s concern, he checked that the children had their tickets in hand to present at the barrier.

When he was a few yards from the exit and clearly committed to leaving, Lily launched her attack. She dashed forward, scattering the children and the dog, and hurled herself at the man’s knees from behind, turning her head to avoid his thrashing heels. He crashed on to his front, flowers flying everywhere, banging his chin on the paved floor.

‘What the hell!’ he roared.

‘Police! You’re under arrest!’ Lily shouted, and before he could struggle free she threw herself down firmly, bottom first, on the man’s neck. She took her police whistle from her tunic and gave three blasts. Where was PC Halliday? With no powers of arrest herself, she could do little without Halliday’s authority. His curses smothered by voluminous layers of Harrod’s tailoring, her prisoner was writhing like a spade-sliced worm. His body bucked strongly, all his senses alert now, muscles working to shift the incapacitating weight without breaking his own neck.

‘Halliday!’ More blasts of the whistle sent the crowd hurrying off in all directions in their eagerness not to become involved in police business.

She heard Stan scream a warning as he lurched forward: ‘Watch it! Knife!’

There was a gleam of metal as the man reached behind and pulled a flick knife from his back pocket. His right thumb worked the switch and an evil length of steel shot out, with the swift flicker of a snake’s tongue.

The sudden descent of a polished half-brogue Oxford on to the man’s knife hand produced a muffled scream. A second application of a leather heel with thirteen stone of well-muscled Englishman behind it elicited more yells and oaths. The crushed fingers spread, their grasp on the knife broken.

Lily’s eyes followed the immaculate shoe upwards along an elegantly trousered leg to a dark tweed Norfolk jacket. A hand reached down holding a handkerchief and the knife was taken up delicately by the tip of the blade.

‘You’ll be wanting to preserve the prints in evidence, officer,’ suggested a voice whose assurance echoed the quality of the tailoring. ‘This weapon may well have been used in previous crimes.’ The stranger laid the knife at her feet and straightened. Lily noticed that he kept his brogue firmly on the Sparrowhawk’s hand.

She was aware of a hatless head of well-barbered black hair, a brown face, clean shaven and confident to the point of unconcern. With an outpouring of relief she began to gabble her thanks. ‘Oh, well done, sir! Lucky for us you were passing. Always a member of the public ready to come up in support, thank God,’ she heard herself say. ‘The Commissioner should hear of this.’

‘I’m sure he will, Miss … er, Officer 1555. One way or another.’ He seemed amused. ‘Ah! And here, a little late, and buttoning up his unmentionables, comes your valiant escort. Let’s hope he has at least remembered his handcuffs.’

The stranger’s voice took on a military tone as Halliday panted up. ‘Constable! Glad you could join us. You nearly missed the party. Arrest this recumbent person on a charge of attempted kidnap of minors, intent to wound a female officer of the law, uttering obscenities in a public place and littering the environs of the station. And anything else that occurs to you.’

He stepped aside and retrieved an untrampled white rose stem from the floor, broke off the bloom and stuck it with a flourish into the band of Lily’s hat, which had remained firmly in place throughout the proceedings. ‘Oh, and let’s be sure not to forget proxenetism,’ he added. ‘I’m sure a little research will confirm: proxenetism. Cuff the villain and take him to the local nick. You may give my name as a witness of events.’

‘Sir! Yes, sir!’ Halliday grunted, hauling the prisoner’s arms behind his back and clicking on the cuffs. ‘At once, sir!’

‘Dash it. I may have missed my train,’ grumbled the military man and, snapping off a gracious salute to Lily, he picked up his overcoat and briefcase and marched off at the double. Lily watched him go, mortified that she hadn’t thought to return his salute. Still, with her right hand firmly entangled in the Hawk’s greasy hair in the prescribed controlling hold, the other clutching her whistle, perhaps the gentleman wouldn’t have expected it.

Halliday turned his attention to Lily. ‘Proxy what was that?’ he said. ‘What was he on about?’

‘He meant procuring. Getting hold of young children and exploiting them for felonious purposes. It’s from the Latin word for pimping. We’ve collared ourselves a predator, Halliday. A sparrowhawk. But that chap – the country gent with the nifty footwork and the nice smile – what did he say? Use his name? I didn’t hear him give one. Should we—’

‘He doesn’t need to give it. Everybody knows him! Commander Have-a-go-Joe Sandilands,’ Halliday groaned. ‘That’s who you were showing off for. Interfering sod! Nice smile? Huh! And you’re trying to tell me you didn’t know him? Pull the other one!’

‘No, honest, Halliday, I didn’t.’

‘Well, you can get up now, 1555 – the prisoner can’t breathe. And your audience has slung its hook. Take that silly bloody flower out of your hat! What do you think you look like? Gawd! I was only in the gents for a minute,’ he protested. ‘He got my number. I saw him looking. That’s my police career over.’ He glowered at Lily. ‘But I’ll tell you something, Miss Showoff, if I go down, I’ll take you with me. There’s things they ought to know about you.’

Lily wasn’t going to allow his threats to dampen her triumph. ‘He got my number too,’ she said. ‘I don’t think that was a man who misses much. But first things first – never mind this villain …’ She gave one last triumphant bounce on the Hawk’s head before she struggled to her feet. ‘And never mind the commander. Where are those children?’

‘It’s all right, I’ve got ’em safe,’ said Stan, appearing with a child firmly in each hand. ‘While the PC’s organizing that piece of filth’s accommodation I’ll just give these two nippers a glass of milk and a cheese sandwich. They look as though they haven’t eaten for a week.’ And, turning to the wide-eyed pair: ‘Welcome to London, kids. I think that’s enough excitement for one day. Come along o’ me and this lady policeman. Naw – don’t you fret about the dog. We’ll see he’s all right. You’re all going to be all right.’

Chapter Four

September 1922

In the warm intimacy of the rear seat of a London cab, Admiral Lord Dedham stretched out his long legs and adjusted the scabbard of his dress sword so as to be sure not to snag the trailing chiffon gown of the woman by his side. It had been a long, hot evening filled with far too many blood-stirring speeches – the most incendiary of them coming from his own lips, he readily admitted. He’d received a standing ovation and that sort of thing always went to the head however tight one’s grip on reality; he’d taken on board too much adulation and too many drinks for comfort. He was longing for the moment, soon approaching, when he could relieve his chest of its cargo of medals and slip out of his much-bedecked dress uniform.

But until that blissful moment arrived, he was more than content with the present one. Even at his time of life – which he thought of as ‘vigorous middle age’ – the admiral still found that the capsule of darkness to be found in the back of a taxi, lightly scented with gardenia, good cigars and leather, sliding secretly through the roistering crowds of central London, had its enlivening effect. It had been even more invigorating in the swaying hansom cabs of his youth but his ageing bones could never regret all that bouncing about over cobbles. He reached out and seized the white-gloved hand left invitingly close to his on the banquette and lifted it to his lips with practised gallantry, a wary eye on the driver.