Karen Pelly is the ambitious and sometimes neurotic junior police officer of Dog River. For many years until promoted, she was referred to as "Rookie" by her superior officer, Sergeant Davis Quinton. Hard-nosed, she's a perfect foil to Davis' sensitivity. Born in 1979, ("Shirt Disturber") before becoming a police officer, she ranked fifth in Canada in the sport of static apnea, with a personal best of more than six minutes. A fitness buff, Karen is also a super table hockey player. By 2014, Karen is married and pregnant with her first child. She's portrayed by Tara Spencer-Nairn.
Karen and Davis argue about whose police cruiser is "Car One" and are thrilled that Lacey has opened the Ruby Cafe and is serving good coffee. Lacey offends Davis when she overturns her Aunt Ruby's free coffee policy for Dog River's police officers, which places Karen in an awkward position when she offers to pay for coffee. Karen solves a mystery that involves Brent and Hank having painted the town's water tower when they graduated in 1986.