Subacute, painful weakness is a common problem encountered by neurologists and can be associated with systemic symptoms. The patient presented with 6 weeks of progressive neuropathic pain followed by sensory changes and distal-predominant weakness. This case reviews the broad differential for such a presentation and a comprehensive, stepwise approach to diagnosis. Particular attention is paid to the potentially treatable polyradiculoneuropathies, including more recently recognized immune-mediated etiologies. Through this stepwise approach, we review how a definitive diagnosis was made.