MINOR SUPER-HERO 048: MISS X

(Mystery Men Comics 019, 1941)

Miss X is a pretty good example of the Female Guest Star Hero, an infrequent heroic archetype with a clearly identifiable arc: start out mysterious and hypercompetent and become less competent as the hero learns more about them. Our only other example so far is Clock ally the Orchid, but Miss X here is helpfully providing us with a three-issue speedrun of the archetype as illustration:

Issue 1, Mystery Men Comics 019: When her sister is killed by foreign spies (after helping them a little but not a lot) and unnamed honours chemistry student sets out to help Lieutenant Drake of Naval Intelligence round them up. Hero knows nothing; Miss X saves the day basically on her own.

Issue 2, Mystery Men Comics 020: Miss X returns in the next issue to help Lt Drake battle a trio of spies. Drake still knows little about her but her major contribton is now being the one who smacks around the lady spy. 

Issue 3, Mystery Men Comics 021: Captured and unmasked by a trio of weirdos, Miss X loses all mystery. She does get to deck the fourth, lady weirdo but this is it for her crimefighting career.