- ALTEREGO
- Sasha Fierce for Beyoncé, once
- Scarlet Witch, for Wanda Maximoff
- Clone?
- Green Hornet, to Britt Reid
- Hyde, to Jekyll
- Literally, "other self"
- Oswald Cobblepot, vis- -vis The Penguin
- Superhero's cover
- Bruce Wayne, to Batman, e.g.
- Clark Kent, to Superman
- Very close friend
- Drag name, for example
- Bruce Wayne, for Batman
- Batman, for Bruce Wayne
- Second self
- Bruce Wayne, for one
- Intimate confidante
- Half a superhero's identity
- *Sasha Fierce, for Beyoncé
- Hannah Montana, for Miley Stewart
- Secondary persona, or what's hidden in the answers to starred clues
- Self-made person?
- Superman, to 47 Across
- Part of many a superhero's life
- Jekyll, vis- -vis Hyde
- Inseparable friend
- Cicero's "second self"
- Secret identity
- Another of your facets
- Lone Ranger, to Tonto
- Peter Parker, for one
- One's other self.
- Mr. Hyde to Dr. Jekyll.
- Bosom friend.
- Constant companion.
- A very close friend.
- A second self.
- Close companion.
- Boon companion.
- One's double.
- Confidant.
- Other self
- Perfect deputy
- Trusted friend
- Other I
- Second shelf
- Mr. Hyde, e.g.
- Sidekick
- Bruce Wayne, to Batman
- Clark Kent, for one
- One of the "three faces of Eve"
- Substitute
- Perfect substitute
- A different you
- Holmes to Conan Doyle, e.g.
- Tony Clifton, to comic Andy Kaufman
- Captain Marvel, to Billy Batson
- Doppelgänger
- You again?
- Bosom buddy
- Hannah Montana, for one
- Secondary identity ... or what can be found in 18-, 27-, 40-, 54- and 66-Across
- Norman Bates or his mother, in "Psycho"
- Second person?
- Ziggy Stardust vis-à-vis David Bowie
- The other you
- Second half?
- This isn't who you really are
- Pee-Wee Herman vis-a-vis Paul Reubens, e.g.
- Self production?
- Mr. Hyde or Hannah Montana
- Evil twin, perhaps
- Tuxedo Mask, for Mamoru Chiba
- Secondary personality
- 19-Down, for one
- Tony Stark, to Iron Man
- Hannah Montana, to Miley Stewart
- Ms. Marvel, for Kamala Khan
- Sasha Fierce, for Beyonce
- Diana Prince, for Wonder Woman
- Jennifer Walters, for She-Hulk
- Other side
- Nurture counterpart, in child development
- Mr. Hyde, for one
- Peter Parker or Miles Morales, or, as an imperative, a hint to the circled letters
- Diana Prince, to Wonder Woman
- Hyde, e.g.
