7 burning questions we have after Strangers episode four

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Here are all the big questions we have after episode four of Strangers:

1. Who "framed" David and attacked Jonah?

Poor clueless Jonah managed to blunder straight into danger at the end of episode four, whipping out his phone (charged, for once) to call the police while David Chen (Anthony Wong) pleaded with him to just shut up and listen. Unsurprisingly, someone stepped out of the shadows to hit Jonah over the head and knock him out cold.

At this point, to be honest, we have pretty much no idea what's going on. Who delivered the knock-out blow? Why didn't they do it before he actually called the police? And why does Jonah have ANY trust in the police, considering they "lost" his wife's body, tampered with his voicemail and clearly covered up Megan's murder?

Then there are the questions about David. Jonah found him on a darkened yacht in a marina in Macau, just after he'd been at the casino with Kai Huang – with Reza's body on the floor next to a gun. Of course Jonah jumped to the conclusion that David had shot him.

However, David insisted that he had been "framed". If so, who by? Could it be triad gangster Kai Huang (Jason Wong)? Or his boss? Or perhaps the police themselves? We're stumped.

2. What's the connection between David and Kai Huang?

A recap: Kai is a triad gangster who works in organised crime. In episode three Jonah managed to get hold of footage linking him to the truck which smashed into Megan's car. We've also seen him give instructions to Reza to find out what Sally Porter knows, and we've seen him take delivery of Jonah's stolen passport.

But now we also know that he was the man David Chen was "colluding" with when he was a police officer, a scandal which got him fired and labelled a traitor. In episode four, Jonah was understandably upset to see David sitting at casino table gambling with Kai.

There must surely be an explanation behind their continued relationship, and how this all relates to Megan?

3. What was Reza up to - and who shot him?

Reza (Ryan McKen) had a warning for Sally Porter (Emilia Fox) when she demanded the name of the person who had her fiancé Ben killed: "He killed him, like he kills me if he finds out what I'm doing."

What was Reza up to? Was he really prepared to hand over information about Ben, in return for papers and a visa to the UK? Or was this a bluff? After all, it was Kai who sent him to track Sally, and we also saw him on the phone giving an update: "We need to talk about her."

The next time we saw him, he was lying (apparently dead) on the floor of a yacht in the Macau marina. So did his boss find out he was pursuing his own agenda with Sally and have him killed? Or was this related to David? So many questions...

4. Why did Megan have $5 million to give to Lau?

What would you do if you became a millionaire overnight? Lau Chen (Katie Leung) had a chance to answer that hypothetical question when solicitor Robin Liu tracked her down and transferred her mum's secret joint account into her name. Her first thought was to get a fancy camera for her girlfriend and to buy drinks for the whole bar, which is pretty sweet.

But where did this $5 million come from? We can only assume that it's the proceeds of organised crime. It may also be connected to Megan's fake passports for her and her daughter, hidden behind the bath panel at Poto-O-Bay. Lau herself seems worried about her surprise inheritance.

5. Who is Michael's source?

Michael Cohen (Anthony Hayes) stuck to his guns in episode four, refusing to reveal the name of his source who told him Ben's "suicide" was a murder. Sally Porter was unimpressed – but you have to admire his journalistic integrity.

His refusal meant Sally wouldn't give him access to Ben's flat, phone and belongings. But what was he hoping to find there? What does Michael know, and what isn't he telling?

6. Is Rachel telling the truth about her relationship with Megan?

Political hopeful Xiaodong Xo's "number two" is Rachel Hargreaves (Raquel Cassidy). While she initially pretended not to know who Jonah was, once they were alone she admitted she had actually been friends with Megan during their early days together in Hong Kong.

Rachel said she and Megan drifted apart, because their respective husbands (Michael Cohen and David Chen) were jealous of their friendship. But while Jonah seemed prepared to accept this explanation, we suspect there is more that she's not telling.

What if the two women lost touch because of their different career paths rather than their jealous husbands? Rachel went to work with Xo (Kenneth Tsang), head of a property empire and target of Lau and the student protests. Meanwhile, did Megan get caught up in Hong Kong's criminal underworld? We can only speculate, but Rachel's story seems incomplete.

7. Is Becky betraying Lau?

Becky (Kae Alexander) is officially Up To Something.

At the end of the previous episode she tried to tell new girlfriend Lau about the anonymous threatening text messages she'd been receiving, but was interrupted and never made her confession.

Has she now decided not to tell Lau? And is the blackmailer demanding information about Lau herself?

"I'm with her now," she told someone down the phone. "I said I would, so I will. If you don't believe me, find someone else."

Could this be connected to the money Lau has just inherited? One thing's for sure: it will suck pretty badly for Lau if Becky betrays her, given she's just lost her mum and found out her mum had a secret English husband. Tough break.

Strangers continues on Mondays at 9pm on ITV

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