Place it just before a reveal or flashback, then follow the date with the Bruh Sound Effect when the answer is anticlimactic, or with Emotional Damage when the date turns out to matter more than expected.
Sobre este som
This is a four-second spoken clip that names December 21, 1972 in Korean. The exact date sounds oddly weighty on its own, giving the listener a puzzled, curious feeling, as if a forgotten detail has suddenly surfaced. It works because the specificity suggests meaning while leaving the reason for that day completely open.