The Hallmark Channel, a highly watched cable network, is known for its consistently idealistic portrayals of romantic relationships. Despite its popularity, no research has examined whether increased viewership of Hallmark movies covaries with endorsement of relationship beliefs. According to cultivation theory, what we watch impacts our beliefs and perceptions of reality. Additionally, the Differential Susceptibility to Media Effects Model (DSMM) proposes that certain variables, such as developmental (i.e., age, relationship length) and dispositional factors (e.g., attachment style, gender), may make certain viewers more or less susceptible to the effects of media viewership. Based on this grounding, the main purpose of this study was to determine if watching more Hallmark movies is associated with endorsing certain beliefs about romantic relationships and opposite-sex friendships when controlling for several susceptibility factors. A nationwide sample of heterosexual, married participants (N = 279) completed measures of Romantic Beliefs, Implicit Theories of Relationships, and beliefs about opposite-sex friendships and reported on their media consumption. More frequent Hallmark movie viewership was associated with increased endorsement of several relationship beliefs, above and beyond susceptibility factors (e.g., attachment, relationship length) and daily television consumption. Specifically, greater Hallmark movie viewership was positively associated with greater endorsement of multiple unrealistic relationship beliefs, destiny beliefs, and believing that opposite-sex friendships are problematic. The findings of the current study provide further support for cultivation theory and DSMM.