Wonder Woman has had more than her share of encounters with doubles. Here, the 1940s original (bondage-happy, as always) encounters a duplicate who is her mother, Hippolyta, secretly involved in a plot to save her daughter's life. Fortunately, "comic book blindness" prevails, and Diana doesn't recognize her own mom behind that little mask.
The 1960s brought revisions to the character's history (Hippolyta is now a blonde), and the adventures of a young Diana, already wearing a version of her future outfit, became popular. Eventually, the writers developed a bizarre storyline that had three versions of the same characters-- Wonder Woman, Wonder Girl, and Wonder Tot-- coexisting at the same time. Wonder Girl eventually headed off to join the Teen Titans, where she was retconned into an entirely different character.

From the early 60s to the mid-80s, the Golden and Silver Age Wonder Women lived on alternate earths. These versions of the characters met for the last time in Crisis on Infinite Earths, DC's 1985 housecleaning exercise. The retconned and matured Wonder Girl appears at left, behind the Earth 1 Wonder Woman.