In the United States, entertainment-education (E-E) initiatives in primetime television that provide public health information are at risk for diminished impact due to the media-saturated environment in which they must compete. One strategy to overcome this limitation is to use multiple primetime TV shows to reinforce similar health messages in multiple storylines. The current study explores such an approach by evaluating the impact of two separate breast cancer genetics storylines featured on two different TV programs as the result of outreach to writers and producers. These storylines aired within approximately 3 weeks of each other on the popular medical dramas, ER (NBC) and Grey's Anatomy (ABC), and included information about the BRCA1 breast cancer gene mutation and the risks it poses to women who test positive for it. The evaluation used data collected from a panel sample of 599 female survey respondents at three points in time. Results show that while the individual storylines had a modest impact on viewers' knowledge, attitudes, and behaviors related to breast cancer, combined exposure seemed to be most effective at changing outcomes. Implications of our findings for future E-E interventions and evaluations are discussed.