This case study examines the 2014 Isla Vista attacks through an integrated behavioral threat assessment framework, synthesizing developmental history, psychosocial stressors, digital communications, and pre-incident behaviors to illustrate the convergence of multiple warning indicators. Drawing on investigative reports, personal writings, video manifestos, and collateral interviews, the analysis highlights the subject’s longstanding grievance, social and sexual marginalization, fixation, pathologized entitlement, and progressive identification with prior attackers. Particular focus is given to the escalation of hopelessness, last-resort ideation, and leakage behaviors in the months preceding the attack, alongside failures in system coordination and opportunities for earlier intervention. The case underscores how clustered warning behaviors across multiple domains—cognitive, emotional, communicative, and operational—can signal accelerating risk, and it demonstrates the importance of structured, multidisciplinary assessment models for evaluating complex, evolving threat trajectories.