"the __ Knows," Line Spoken in 1930's Radio Series

This page is the CodyCross answer for the clue below from Ballroom Dancing, Group 1928, Puzzle 5 (Passionate).

Question is: "the __ Knows," Line Spoken in 1930's Radio Series

and the answer is: SHADOW

Word Meaning:

SHADOW — A dark image projected onto a surface where light (or other radiation) is blocked by the shade of an object.

Definitions from Wiktionary.

"The __ knows," line spoken in 1930's radio series — CodyCross Answer | CodyCross Solutions