Here's what was actually happening on those film sets in the 1950s.
Before every single shoot, the makeup artist started with the under-eyes.
They knew what most people still don't: this one small area decides whether a face reads fresh and awake or tired and drained. Get it right, and the rest of the face follows.
So they used something revolutionary at the time, temporary eye tighteners.
These temporary eye tighteners had film forming silicates consisting of millions of micro-tightening minerals.
And as these micro-tightening minerals dried, they'd connect with one another, forming a film that kind of acted as a second skin. Gently pulling in the hollows under the eyes — the very hollows that create that shadow effect in the first place.
These minerals also had a sheer-tint which adapted to the skin, neutralizing the darkness of the blood cells beneath the thin under-eye skin — instead of sitting on top of it the way concealer does.
All happening in under 90 seconds.
Dark circles, gone. Shadows, gone. Under cameras that showed everything.