7 crucial questions we have after Strangers episode 3

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If, like Jonah, you need some help getting your head around it all, you're in luck. Here are the seven big questions we're still pondering:

1. Was David responsible for Megan's murder?

"I think he was involved in Megan's murder," Professor Jonah Mulray (John Simm) breathlessly tells his consulate contact Sally Porter (Emilia Fox) down the phone, after having finally put two and two together, gone home and googled "David Chen police traitor".

According to Jonah, it all makes sense: Megan was scared of David. That's why she had American passports for her and Lau, in order to flee the country. That was why she left Jonah that cryptic final voicemail, and it was also why she had the poster above her bed in Hong Kong. (The exact significance of the poster is unexplained.)

And sure, it' not looking good for David at the moment. The Google search reveals that he was convicted of corruption for supposedly working with a triad contact, part of a powerful organised crime syndicate. That contact was Kai Huang (Jason Wong).

Now – with the exception of his former partner Felix Chong (Thomas Chaanhing) – his old police colleagues treat him as a traitor, and shun or taunt him in the street.

If David was involved in some way, that could explain why he was reluctant to go to the depot with Jonah to find the garbage truck, although he did go in the end – and offered to bribe the man at the depot £5,000 for his help.

But here's something odd. When Jonah and David watched the stolen CCTV footage, David failed to identify the man caught on camera getting out of the garbage truck – even though this was the very same man he was convicted of working with as part of the triad trial. He actually went to his former police partner Felix for the identification.

After identifying the man as Kai and telling a baffled Jonah that this man was involved in the triad, Felix asked David: "He has no idea, does he?"

David may or may not be responsible for Megan's death, but he sure knows more than he is prepared to tell Jonah...

2. Who is Kai and what is the "triad"?

Kai Huang (Jason Wong) is a low-level operative in organised crime, and so far in the story he's been a very shadowy figure. He sees himself as a gangster and has great ambitions, but clashes with his gangster father Choi Huang (Peter Lau) when he goes to pay him his money.

Now we know that Kai is the one instructing Faraz, and also that he was the one caught "working" with David Chen. But how is he involved with Megan's death?

Kai seems to be connected to a triad, aka an organised crime syndicate. The triads in Hong Kong operate along traditional lines (a bit like the mafia) and take part in – for example – fraud, extortion, money laundering, trafficking, prostitution, smuggling, the drug trade and counterfeiting. You'd want to stay well away. But did Megan get mixed up in something dangerous?

3. What does Faraz need to tell Sally?

Information we now know:

• Faraz Reza (Ryan McKen) works for Kai Huang
• It was Faraz who stole the passport from Jonah's hotel (and gave him a black eye), later handing this over to Kai. Faraz also used Megan's stolen credit card
• Faraz desperately wants to get to Europe, specifically to the UK.

In episode three, Kai instructs Faraz to contact Sally: "I need you to speak to this woman, find out what she knows." Sure enough, he shadows Sally through the streets of Hong Kong and corners her in a stairway.

Dismissing her screams of terror, Faraz tells her to come to Wellspring Mansions – and says he can reveal information about her dead (and probably murdered) fiancé Ben. What he wants in return is a visa to the UK.

That makes us wonder: is Faraz really operating on Kai's behalf, or has he seen an opportunity to look after his own interests by striking a deal with Sally?

4. Who is texting Becky?

At the end of the previous episode, we saw someone snap a photo of Becky (Kae Alexander) and Lau (Katie Leung) as they shared their first kiss at a bar. But now there have been new developments – and they're not positive developments.

While on a date with Lau, Becky receives a text from an unknown number on an unknown phone that has somehow made its way into her bag. The first text is the photo of the kiss, followed by messages saying: "Becky. Keep this phone. We will be in touch. We are watching you."

Becky is disturbed by the threatening messages but decides not to tell Lau. However, later that night she receives another message, along with her prison mug shot: "If you don't do what we say you'll go back to jail."

She starts to tell Lau – but is interrupted by a knock on the door...

Is this to do with her protest against Xo? Or is whoever's texting her trying to blackmail Becky into betraying Lau? Does she know who's on the other end of the phone, or is she as in the dark as we are?

5. What does the solicitor have for Lau?

A man calling himself Robin Liu knocks on Lau's front door late at night, telling her that he's a solicitor who has been urgently trying to contact her.

Inconveniently (but perhaps conveniently for the plot), he interrupts Becky's confession about the mysterious texts to tell Lau that he has "something for you from your mother." But what is it?

6. What's going on with Michael's ex-wife and Xo?

Surprise connection: Michael's ex-wife works for Xo Xiaodong, the businessman Lau and co have been protesting against. She's in charge of his election campaign for Chief Executive of Hong Kong.

Michael and his ex are not on good terms (to say the least) but they do have a child together – a young daughter called Mae – so they must remain in each other's lives.

It's clear that Michael blames Xo for the collapse of their marriage, resenting his then-wife for spending all her time and energy on her boss who "always came first". And having seen them together in his high-rise office, you have to wonder: does the relationship go deeper than boss and employee?

It also emerges that Michael's ex-wife knew Megan and her friends, at least vaguely. She's done a bit of digging and discovered that the triad is involved – information she passes on to Michael as a warning.

7. Is Arthur Bach up to something at the consulate?

Sally Porter's boss at the consulate (played by Tim McInnerny) has developed a sudden interest in Jonah's plight. But why?

Ostensibly, he wants to help Jonah locate his wife's body, which has gone missing from the morgue. Bach suspects the Hong Kong police are corrupt, and the only way forward would be for Jonah to "go public" with the information about Megan.

He may be genuine, but what if he's playing a game of his own?

Strangers continues on Mondays at 9pm on ITV

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