Hate, an intense negative emotion, can disrupt and damage interpersonal relationships following transgressions. Despite its destructive potential, the psychological mechanism that fuels hate remains poorly understood. Anger has been identified as a primary component of hate, yet anger and hate differ in their appraisal tendencies and motivational goals. This raises a critical question: how does anger contribute to the emergence of hate? To address this, the present study examined the interplay among anger, anger rumination, grudge, and hate. A total of 740 participants completed self-report measures of these constructs. Using network analysis with regularization methods, followed by serial mediation analysis, we mapped the structural relations among the variables and tested directional pathways. Network analysis revealed grudge as the most central and influential variable showing the highest strength, betweenness, and closeness indices. Further, serial mediation analysis revealed that the relationship between anger and hate is serially mediated by anger rumination and grudge. These findings suggest that when anger is not regulated effectively, it may intensify through ruminative thinking and unresolved grudges, resulting in hate. The findings highlight the importance of targeting the maladaptive anger process, particularly rumination and unresolved grudges, in interventions designed to prevent interpersonal anger from transforming into hate.