This takes place some time between the end of Series 1 and the beginning of Series 2. Note: the island of Santiago is entirely fictional.

"No, Dwayne, you can't build a house on Fenchurch Street Station!" Richard Poole sighed in exasperation. It was a blisteringly hot, sultry and irredeemably dull afternoon and he had spent the past two hours trying to teach his team to play Monopoly. It really wasn't that complicated – he had mastered the rules by the time he was seven after all - but somehow Dwayne, Fidel and Camille appeared to find it baffling. Dwayne, he was sure, wasn't even trying. He was lounging back in his chair, taking long swigs from his bottle of beer. Fidel was doing his best of course but simply lacked aptitude. And as for Camille, she was clearly bored: she had been alternately wriggling impatiently in her chair and pacing up and down the veranda in frustration.

"It's so slow – we've been playing for hours and no-one is winning! Can't we stop now? See, I have landed on Mary Le Bone Station, should I buy it?" She enunciated the name carefully.

"It's Marley Bone, Camille, not Mary Le Bone."

"How can it be Marley Bone when it's clearly written as Mary Le Bone – it's obviously a French name!" She pouted provocatively.

"Well I can assure you Marley Bone is how it is pronounced. Now can we please get back to the game?"

"What a stupid language English is – nothing is ever pronounced as it is written!"

Richard was about to retort with some disparaging remarks of his own about the impossibility of the French language, when they were interrupted by a heavy tread on the stairs, and the urbane face of Selwyn Patterson peered round the door.

"Ah. Good afternoon, team. I see you are hard at it as usual."

They sprang to their feet like guilty children.

"Yes, Sir, well, er, it's extremely quiet – which is good of course because no-one is committing any crimes – and, um, well I thought that as we had caught up with everything we should spend a little time, um, you know, team building." For the hundredth time, Richard cursed himself for appearing so flustered and inept. The Commissioner always had that effect on him; he suspected that Selwyn Patterson was well aware of it and deeply enjoyed the discomfort which he inflicted.

"Quite so, Inspector. He surveyed the scene with a benign smile. "May I have a word with you and Sergeant Bordey, please?"

"Certainly, Sir", and he indicated to Dwayne and Fidel that they should withdraw. The three of them sat back down at the Monopoly table.

What now? he thought. He ran his mind rapidly back over the past week's work: nothing extraordinary there, nothing to merit any kind of reprimand – just a few small local crimes cleared up. He glanced across at Camille, who shrugged imperceptibly. So she didn't know what this was about, either. But the Commissioner always arrived with an agenda – not usually a welcome one – and he braced himself for whatever was to follow.

"What do you know of the island of Santiago?"

Richard was astonished. What sort of opening was this? "Well, er, not very much, Sir" he admitted. "I believe it's about 30 miles or so off the coast of Jamaica?"

"Yes, that's right. It was originally Spanish - hence the name – but British for hundreds of years. It has been rather slow to develop – it relied on its fishing industry for years - but the tourists are now coming and the resorts are growing. An island ripe for exploitation. And that's what we rather think is happening."

The Commissioner paused, and Richard wondered what on earth a remote island on the other side of the Caribbean had to do with him. The puzzlement must have been written on his face, for Patterson continued.

"Yes, I am sure you and Sergeant Bordey are wondering why I am telling you this. A few days ago I had a phone call from the Commissioner of the JCF. That's the Jamaica Constabulary Force, Inspector. They look after the policing of Santiago. The JCF believe that the island is being used as the hub of a sex trafficking and money laundering ring and they think it is being run by a group of Chinese who have been staying on the island for some time. They want someone to go in under cover and try to find out if their suspicions are correct, and they have asked for you, Inspector, because of your Chinese language skills."

Richard nearly fell off his chair in shock. "Me? But I've never done any undercover work!"

"I am well aware of that, and that is why I have only agreed on the condition that you are accompanied by an officer who is experienced in undercover work– Sergeant Bordey."

"But …" Camille could hardly get the words out. "I mean, do you think Inspector Poole is, er, entirely suited to undercover work, Sir? It's very different from what he does here on Saint-Marie." That was putting it mildly, she thought.

"That remains to be seen, Sergeant, but I am sure you will do your best to prepare and guide him."

She fell back, speechless for once. At any other time Richard would have been amused by the unmistakeable look of horror on her face, but not today. He desperately cast around for something, anything, that would spare him this unlooked-for fate.

"But how can both Sergeant Bordey and I be away from the station at the same time, Sir? If anything serious should happen – a murder, for instance – Sergeant Best is not experienced enough to cope. Perhaps Sergeant Bordey could undertake the assignment on her own?"

The Commissioner turned to Camille. "Seargent Bordey, do you speak Chinese? Could you eavesdrop on a conversation or read documents written in Chinese?" She shook her head mutely. "You see, Inspector, Sergeant Bordey could not manage without you. And I have already made your point to the Commissioner in Jamaica, who has kindly agreed to lend us one of his senior officers while the two of you are away."

Richard felt himself being swept away by an irresistible current. He clung on by his fingertips. "But these Chinese, Sir, they could speak any one of a number of Chinese languages. If they come from Shanghai, for example, they will speak Wu, and I only know Mandarin, and I haven't spoken that for more than 20 years! I really don't think I will be much use." He tried not to plead but knew he was perilously close.

"Calm yourself, Inspector, I have it on the best of authority that the Chinese on Santiago are from Beijing and will therefore presumably speak Mandarin, so there should be no problem. And you do appear to be the only officer in the Caribbean with a knowledge of Chinese - I would not otherwise have agreed to the assignment."

Richard saw his last hope evaporate. He slumped glumly in his chair. Camille was still looking too shocked for sensible conversation. The Commissioner's tone was bracing.

"Come now, Inspector, look upon it as a good chance to widen your experience. You have done good work here on Saint-Marie and now we have an opportunity for the island to really punch above its weight. I am sure you realise how very important this could be to our future role in the policing of the Caribbean. I am relying on you both not to let me and the island down!"

He got up to leave. "You will be leaving in a fortnight. I will have all the details of your undercover roles drawn up and sent to you. By the way, you will be posing as a British businessman on holiday with his French wife." Ignoring the gasps of dismay from both Richard and Camille, he continued urbanely. "I understand that the climate is a little less oppressive at this time of year on Santiago, so you may welcome the change of scene. I wish you an enjoyable and successful trip."

The Commissioner picked up his hat and paused on the way out. "And by the way, Sergeant, I should buy Marylebone Station if I were you – it should be a good investment."