The word “zany” comes from Zanni, notorious tricksters introduced in 16th-century commedia del’arte. Among the Zanni family is Scapin, a playful servant who lives up to his name by escaping from the sticky situations he orchestrates. First staged in Paris in 1671, Molière’s comedy Scapin’s Deceits presents the title character as a pompous liar who ultimately saves the day. In the 1990s, “clown prince” Bill Irwin joined forces with the late writer Mark O’Donnell to update Molière’s farce. Following the squirrelly valet into a tangled web as he assists two young men who’ve fallen for “unlikely and penniless beauties,” the duo’s Scapin brings the language up to speed but maintains the work’s original structure. Matthew Byron Cassi directs Brendan Spieth in the Classic Theatre’s production.