This episode introduces Traylor Howard in the role of Monk's new assistant , single mom Natalie Teeger. Monk (Tony Shalhoub) meets Natalie in a typically unorthodox fashion, after she kills a burglar who had broken into her home--apparently for the purpose of stealing her pet fish! Investigating the reasons behind this bizarre set of circumstances, Monk follows the clues to a science fair. . .and in the process draws ever closer to Natalie, whom he hopes will fill the void left in his life when his former nurse-assistant Sharona Fleming left San Francisco to remarry her ex-husband in New Jersey. ~ Hal Erickson, Rovi