<P> She started acting with appearances in TV shows . </P> <P> Then Wells played Jennifer Parker, Marty McFly's girlfriend, in the 1985 film Back to the Future . She almost did not end up in the first film of the successful franchise . According to Wells, in an interview with Yahoo.com online entertainment series "The Yo Show", she had been cast, but a pilot she had done for ABC had been picked up, and she was contractually forced to drop out of Back to the Future . During that time, Eric Stoltz had been shooting for five weeks in the role of Marty McFly . Melora Hardin was slated for the role of Jennifer, though she never actually filmed any scenes . The producers halted filming and replaced Stoltz with Michael J. Fox . By then, Wells' pilot had been finished and she was recast as Jennifer, now shooting alongside Fox, never having filmed a frame with Stoltz . </P> <P> After her mother was diagnosed with cancer, Wells said family took precedence and told the studio she would not be available to reprise the role for the two sequels; actress Elisabeth Shue replaced her . </P> <P> That same year (1985), Wells co-starred in Stop the Madness, an anti-drug music video sponsored by the Reagan administration, featuring several famous musicians, actors and athletes . The following year, she appeared in the TV movie Babies Having Babies, and the short - lived series Fast Times, a TV adaptation of the 1982 film Fast Times at Ridgemont High (Wells played Linda Barrett, portrayed by Phoebe Cates in the film). Following Fast Times, she did not again appear on - screen until the 1996 independent film Still Waters Burn (released on DVD February 12, 2008). </P>

Why did the first jennifer leave back to the future
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