The new season of the USA network's Monk, starring three-time Emmy winner Tony Shalhoub and premiering Jan. 19, will feature guest appearances by Studio 60's Steven Weber (as a radio shock jock suspected of murder), Two and a Half Men's Holland Taylor (as Natalie's mother), Andy Richter (as a strange new buddy of Monk's), Charles Durning, Sean Astin and Desperate Housewives' Ricardo Antonio Chavira.