What mood did Orwell create before writing about Julia and Winstons capture in 1984?

As the scene progress closer to the place where they are captured, the mood increases
in ominous undertones.

spends a great deal of time just prior to the capture
reading Goldstein's book. In it, he ponders the Thought Police, his government's necessity of
DOUBLETHINK, and how people are controlled by insanity.

He dozes withand then
wakes to a song being sung from below: "It was only an €˜opeless...