As he anxiously paced the concourse at Chek Lap Kok, rehearsing yet again his unconvincing version of a debonair demeanour, his phone buzzed.
Ethan glanced at the screen - it was Yui-man. Since their childhood friendship on the Ki Lung public housing estate, the pair's lives had gone in very different directions. The combination of an unstable home life and his own gentle nature left Yui-man ill-equipped to stand up to the threats of the local gang. His subsequent progress from messenger boy to fall guy was swift. While Ethan was now a scholarship student at St Jude's International School, Yui-man had spent his 15th birthday in a Young Offenders Institute.
During the holidays, however, the pair had got together and talked for the first time in years, leaving Ethan determined to help in any way he could.
But now, as the glass doors from the customs check slid open, Ethan killed the call without picking up. Because when he saw Maya standing there, all sparkling eyes, sun-bleached hair and golden skin, he didn't have the breath left in his body to even mutter "Hello".
"What do you mean you haven't found anything?" Chan raged at the private detective, his clenched fist hovering above the scale model of a soaring block of luxury flats and shops that stood in the corner of his office. Seething with frustration, Chan only just managed to stop himself from destroying the only concrete manifestation of the project he had poured everything into.
Despite owning most of the properties in the decrepit building that currently occupied the site of his proposed skyscraper, one old man had prevented him gaining the 80 per cent control he needed to take over and demolish the building.
However, Chan remained certain the old man couldn't have raised the money legally to buy his shop. If they could just expose his crooked secret, they could still force him out.
"But what if there's nothing to find," the detective reasoned.
"Then we create something. And we pile the pressure on the rest of his family until they crack, too."
Monday morning at St Jude's. As they unpacked their school bags into their lockers, Ethan and Maya's mutual absorption was such that they were barely aware of Sam regaling them with tales of his new-found talent as a surfer.
His boasting, however, was cut short by his sister, Jenny. "Puh! You spent more time under the waves than on them," she jeered, before turning to Ethan and Maya. "The instructor said he should have given Sam a submarine not a surfboard."
Before her brother could protest, they were interrupted by the headmistress' commanding tones. "Ethan Tai. My office. Now."
As a bemused Ethan trooped off behind the bustling figure, Sam called after him, "Respect, my man!"
Confronted by a quizzical Maya and Jenny, Sam explained. "Getting into trouble before term has even started? I'm going to check, but that's got to be a new school record."
But the trouble Ethan was in was of a whole different order to that which Sam imagined.
"What?" Ethan gasped, as he stared at the headmistress in shocked disbelief.
"I'm sorry to be the bearer of such bad news but I thought I'd better tell you in person rather than just send a letter home," the Head explained. "I know your mother has been seriously ill and I wouldn't want to jeopardise her recovery with any sort of unpleasant surprise."
"But if my scholarship ends half way through this term then ...," he trailed off.
"Ethan, Ethan. I'm sure we'll be able to work something out - especially for such an able and generally well-behaved student as yourself. Well, at least until the summer that is."
Ethan's gaze travelled desperately around the wood-panelled office as he struggled to absorb what he'd been told.
"But beyond that ..." the Head's eyes glistened with emotion, "... it's out of our hands I'm afraid. Our benefactor says he's no longer in a position to fund the scheme."
In the corridor outside, the Chan twins, Gilbert and Charlotte, were waiting gleefully for a shell-shocked Ethan.
"Get real, you loser," sneered Gilbert, "St Jude's was never meant for the likes of you."
"What?" Ethan muttered, before slowly registering the significance of what Gilbert had said. "How did you know about ..."
"Did you really think our dad was going to carry on wasting his money on you?" Charlotte demanded.
The appalling truth finally dawned on Ethan. "The benefactor ... it's your dad?"
"Was," Gilbert corrected with vindictive delight. "And look at how your grandad showed his gratitude."
Later at the cha chaan teng, Ethan pushed his milk tea away from him, shut his eyes and began, once more, to rub his forehead.
"But the website's still making a big profit, isn't it?" Maya asked, desperate to somehow lift her boyfriend's mood.
"Yeah, but it's not enough. The money we got from selling a share of the site all went on buying Grandad's shop. But then there were the agent's fees, the stamp duty ... and what with the rent on the flat, the day-to-day bills, and Mum's physiotherapy ... there's just no way I can afford the school fees on top of all that."
"But the Head said they'd be able to work something out for the rest of the term, didn't she?"
"Yeah, and I hope she's right. Because I don't want to think about the effect it'll have on Mum if I have to leave St Jude's."
He glanced at his watch and sighed.
Reluctantly, Maya let go of his hand. "You'd better go, hadn't you?"
When he'd heard that Yui-hon's feckless father had once again gambled away his wages, Ethan had been more than ready to stump up the rent money for his old pal.
Now, despite his own worries, Ethan waved away the protests and the outpouring of gratitude. He couldn't bear to think of Yui-hon falling into the clutches of Wai-hung and his gang again.
But as Ethan pulled out his wallet, and as the pair joked about the way they used to share their ice cream money, they were oblivious to the heavy tread of approaching footsteps. The local police station had received a tip-off that a drug deal was going down on the Ki Lung Estate, and sure enough the two officers arrived just in time to see the cash being handed over.
And ... click! ... from his hiding place behind the wheelie bins, Chan's detective captured Ethan and Yui-hon's arrest on camera.
To be continued next week