In almost every episode the audience sees the crime unfold at the beginning and knows the identity of the culprit, typically an affluent member of society. Once Columbo enters the story (he rarely appears in the first act), viewers watch him solve the case by sifting through the contradictions between the truth and the version presented to him by the killer(s). This style of mystery is sometimes referred to as a "howcatchem", in contrast to the traditional whodunit. In structural analysis terms, the majority of the narrative is therefore dénouement, a feature normally reserved for the very end of a story. Episodes tend to be driven by their characters, the audience observing the criminal's reactions to Columbo's increasingly intrusive presence. The explanation for the crime and its method having played out as part of the narrative, most of the stories simply end with the criminal's reaction at being found out. At the beginning of every episode, Columbo's genius was hidden by his frumpy, friendly and disarming demeanor, luring the killer into a false sense of security. In some cases, the killer's arrogance and dismissive attitude allow Columbo to manipulate his suspects into self-incrimination. While the details, and eventually the motivation(s), of the murderers' actions are shown to the viewer, Columbo's true thoughts and intentions are almost never revealed until close to the end of the episode (he occasionally begins to whistle the tune "This Old Man" as the pieces begin to fall into place). Columbo generally maintains a friendly relationship with the murderer until the end. The point at which the detective first begins to suspect the murderer is generally not revealed, although it is often fairly early on. Columbo had a duality of character; the disarming and unkempt detective and the hidden genius sleuth. The genius would sometimes starkly manifest itself through his eyes as it did when Jack Cassidy’s killer escaped from the hand-cuffs in his magic show. Such moments always bode bad tidings for the killer. In some instances, such as Ruth Gordon's avenging elderly mystery writer in "Try and Catch Me", Janet Leigh's terminally ill and deluded actress in "Forgotten Lady", Donald Pleasence's elegant vintner in "Any Old Port in a Storm", and Johnny Cash's enserfed singer in "Swan Song", the killer is more sympathetic than the victim. Each case is generally concluded in a similar style, with Columbo dropping any pretense of uncertainty and sharing details of his conclusion of the killer's guilt.