Strangers - John Simm (2018) - H.K.W.W Yuen Long R.G Filters Building, Yuen Long

The venue where Lau is taken by her kidnappers is an old Hong Kong Water Works facility on the Tuen Mun/Yuen Long district border. For some reason the "Yuen Long R.G. Filter" is no longer on the Film Services website despite their photos of it popping up when you do a Google search. Perhaps they have decided to rebuild it and so it is no longer available? Anyway, it looks like the interior was also filmed on location.

Strangers - John Simm (2018) - Container Port Road South, Stonecutter Island

After Lau has been kidnapped, her kidnapper is stopped by the police because his rear light is broken. Funny thing is though that this place is a dead end. This is the service road that runs underneath Stonecutters Bridge (you can see the bridge at the top of the image) and the car has basically just driven from the dead end by the sea wall when it is stopped. You can see where the road ends behind the car as it is turning. In the second image you can see how close this place is to one of the container terminals.

Strangers - John Simm (2018) - Hoi Chak Street, Quarry Bay

Jonah follows Sally when she leaves her hotel and spots who she is meeting up with along Hoi Chak Street in Quarry Bay. You can just see the square columns of the Kerry Centre in the back left of the second image.

Strangers - John Simm (2018) - Under Bridge Spicy Crab, Wanchai

At the start of Episode 7, the story moves to Mr Xo (played by Kenneth Tsang) who is the favourite candidate for the upcoming Chief Executive "election". Actually, the predetermined nature of the election is even hinted at by one of the characters later in the episode - so much like the real election charade that is undertaken in the real Hong Kong.

We see him eating dinner with his family at a place called Under Bridge Spicy Crab. It's a real place and looks like it has 3 closely clustered premises around Canal Road in Wanchai. The one on film is the one at 421-425 Lockhart Road.