It’s a staple of writing thrillers that the stakes and the difficulties for the protagonist must keep ratcheting up throughout the story. After all, if the protagonist is faced with a difficulty, comes up with a plan to overcome it, and executes that plan seamlessly, there’s not really that much tension/suspense. Heck, there’s not even much of a plot.
There’s a whole raft of things that can be done to thwart the protagonist’s efforts. He can have underestimated the difficul