While media research has long ago acknowledged that watching TV is a social activity, only a few studies have examined the effects of co-viewing on adult reactions to a televised text. In the current investigation, we used social-cognitive theory combined with previous research on the intra-audience effect, audience identification, transportation, and attitude change to develop hypotheses connecting co-viewers’ reactions, co-viewers’ gender, and viewer’s post-exposure attitudes. Participants watched a movie segment that ended in a rape scene. We manipulated their confederate co-viewers’ displayed reaction (enthusiastic or bored) and gender, and subsequently measured perceived co-viewers’ attributions of responsibility for the rape, the viewers’ transportation, identification with the male protagonist, and acceptance of the rape myth (the tendency to attribute responsibility for sexual violence to the victim). Results demonstrated that for those participants who correctly perceived the engagement manipulation, the effect of the confederate co-viewer’s engagement manipulation on rape myth acceptance was positive and significant. In addition, both manipulations had an indirect effect on rape myth acceptance, sequentially mediated through transportation and identification.