Does averting a school attack ensure that the threat of violence has been mitigated? This case study analyzes an averted school attack at a Michigan high school and an act of violence carried out by the averted school attacker three years later. This incident highlights the need for ongoing engagement and management of high-risk persons during and after an averted attack as well as the need for collaborative multidisciplinary interventions to prevent acts of targeted violence that may endure after the initial threat was mitigated.