KAREN Allen is sometimes mistaken for a similar-looking contemporary who played the spunky girlfriend of the hero in another blockbuster trilogy – and who has also been out of the public eye for a while.

Margot Kidder, who is three years older than Allen, was Lois Lane in 1978’s “Superman: The Movie” and its first two sequels.

Kidder, who has bipolar disorder, made headlines in 1996 when she was institutionalized after being found disheveled with her hair cut off, wielding a knife – and raving about imaginary pursuers.

Since recovering, Kidder has regularly worked in theater and on TV, including episodes of “Smallville,” a series about Superman’s teenage years.