Acute hepatitis with severe hepatic failure is an uncommon manifestation of herpes simplex virus (HSV) infection. It has been described in both immunocompromised and immunocompetent patients and is usually fatal. Due to the better survival after acyclovir treatment in a few reported cases, physicians need to be aware of the characteristic clinical abnormalities so that early diagnosis and treatment can be implemented. The authors describe an adolescent diagnosed with Hodgkin disease who developed fatal hepatic failure secondary to acute HSV. Typical signs and symptoms in patients at risk, when there is no other obvious cause of fulminant hepatitis, should lead to early empirical treatment with acyclovir.