Not all missing persons are treated equally. Research shows that certain types of victims are overrepresented in the media, but it is not clear whether these patterns also reflect differences in people’s propensity to help certain types of victims. Therefore, the purpose of this study was to examine whether the characteristics of a missing person’s case influence respondents’ willingness to help find the missing person. Using a 2 × 2 × 2 vignette study (N = 675), gender (male/female) and background of a missing person (western/non-western) and police involvement (yes/no) were manipulated to test respondents’ subsequent willingness to search. We further examined the influence of two-person specific factors among potential searchers: the respondent’s attitude toward searching and levels of perceived positive and negative affect. This study found that, despite a small but significant effect of gender, respondents’ intention to search is primarily determined by affect and attitude, with the former having relatively the strongest influence. Of the two affective states, positive affect had the strongest effect, about twice that of negative affect. Affect not only fully mediated the effects of gender on intention, but also had an independent influence on willingness to help that exceeded the indirect effect of gender. Therefore, it can be concluded that willingness to help find someone depends primarily on the (positive) affective state of the potential searcher than on specific characteristics of the missing person case or considerations regarding the search itself. The study has important practical implications for engaging citizens in missing persons cases.