Books
O, what may man within him hide, though angel on the outward side!
— William Shakespeare • Measure for Measure

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Appearances get treated with suspicion here, since a gentle outward manner can mask something far less kind underneath. The angel comparison heightens the contrast, pairing purity of image with hidden menace. It's a warning dressed as an observation, unsettling because it applies to anyone at all.
Context reviewed