The young docent welcomed the class to the museum, explaining that the east wing was under construction and he’d be leading them to the first exhibit. His fingers leapt to his name tag as he nervously introduced himself as “Liam, a student of the arts.” Then he bade the group follow him. They traversed a vaulted hall lined with hulking objects, each one obscured by a faded tarpaulin. Some of the items stretched across the floor, others cast long shadows on the museum walls.
What technique does the author use to build suspense in the excerpt?