A member of the
Legion of Substitute Heroes.
Lydda Jath is the real name of Night Girl. Lydda is a native
the planet Kathoon, a planet with no sun. She became infatuated
with Cosmic Boy, the then-leader of the Legion of Super-Heroes.
She dreamed of having a power which would allow her to join the
Legion to be with the object of her affection. Her father created
a ray which gave her super-strength, rivaling that of Superboy and
Mon-El.
Lydda, calling herself Night Girl, came to the Legion try-outs, only
to discover that she only possessed heightened strength at night
or in deep shadow. This limitation caused her to be rejected
for Legion membership. She and the other candidates that day decided to form their own
group, the Legion of Substitute Heroes.
Night Girl is romantically involved with Cosmic Boy. She is well-known for wearing her hair in an enormous
bouffant, obviously in a bid to attract Cosmic Boy's attention.