"Supergirl" Introduces Classic Piece of Superman Lore

When White Martians attack a political rally, Jimmy Olsen breaks out a classic piece of Superman lore to call Supergirl to the scene of the battle: The Signal Watch!

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In the comics, the watch traditionally emits a high-pitched sound on a frequency only audible to Kryptonians. It was a gift to Jimmy from Superman, given to the photographer due to his predilection for finding himself in situations where he needed his super-powered buddy tpo bail him out.

"Supergirl," starring Melissa Benoist, Calista Flockhart, Mehcad Brooks, David Harewood and Chyler Leigh, airs Mondays at 8 pm EST on CBS.

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