Brian Dennehy plays a Wambaugh-type cop who has flourished as a novelist. At the moment, however, Dennehy is suffering from a profound case of writer's block. Coming to the rescue, as it were, is professional hit man James Woods. Recently dumped by his boss, above-suspicion business executive Paul Shenar, Woods is anxious to tell his life story to Dennehy, in hopes of striking it rich with a tell-all bestseller. Shenar, however, takes a dim view of Woods' indiscretions, and for a while it looks as though it's curtains for both Dennehy and his teenaged daughter Allison Balson. Screenwriter Larry Cohen has claimed that Best Seller was based on Strangers on a Train.