Herpes simplex virus (HSV) hepatitis is an uncommon cause of acute liver failure (ALF), primarily affecting immunocompromised patients. So far, 148 cases have been published, of which 9 underwent liver transplantation (LT). The reported post-transplant survival is poor, with over 60% dying in the first year. Dosing and duration of antiviral therapy after LT are not established. Concerns include both the risk of hepatic recurrence after LT and emergence of viral resistance during prolonged therapy. HSV DNA plasma levels might be helpful to monitor therapeutic response and guide duration of therapy. We present a case of ALF complicating a primary HSV-1 infection in an immunocompetent host, who required emergency LT. We further discuss the value of measuring serial HSV DNA plasma loads to monitor antiviral therapy.