"The excellent husband of Winnie Verloc saw no writing on the wall"

Rembrandt's Belshazzar's Feast, painted in 1635
Public DomainRembrandt's Belshazzar's Feast, painted in 1635
“The writing on the wall” is an expression signifying a warning of doom or harbinger of imminent danger.

It comes from the Book of Daniel in the Bible, in which divine writing appears during a feast foretelling the fall of the Babylonian empire