Essentially, it was a simple plan that one could call "waiting for the hare at the stump."
The whole thing was actually pretty straightforward: Yang Yi and Kate were to put on a true and false show all the way, luring out the people from Destroyer, while the Dark Night Knight would have their people set up in advance at the train station, Southampton clinic, and the last place Yang Yi and Kate would end up staying.
Simply put, Yang Yi was to walk into one trap after another, waiting for Destroyer's killers to fall into them.
Now, as expected, someone couldn't hold back and made their move, so they fell right outside a clinic that looked quite normal.
Yang Yi thought it would be the Dark Night Knight's people lying in ambush inside, but it turned out they weren't there at all, this was the only detail that didn't match up with Yang Yi's expectations.
