While sinusitis is a common ailment, intracranial suppurative complications of sinusitis are rare and difficult to diagnose and treat. The morbidity and mortality of intracranial complications of sinusitis have decreased significantly since the advent of antibiotics, but diseases such as subdural empyemas and intracranial abscesses still occur, and they require prompt diagnosis, treatment, and often surgical drainage to prevent death or long-term neurologic sequelae. We present a case of an immunocompetent adolescent male with a subdural empyema who presented with seizures, confusion, and focal arm weakness after a bout of sinusitis.