Harwell was a United States Secret Service agent active during Day 9. Before CIA agent Kate Morgan left with Jack Bauer for an undercover mission, Harwell frisked her for weapons. He then handed Morgan her phone and left. ("Day 9: 4:00pm-5:00pm") Later that day, Harwell was patrolling the basement of the Willoughby House when he stumbled upon President James Heller. As Heller tried to distract him, Jack Bauer approached Harwell from the back and knocked him out. He then dragged Harwell into the bathroom. ("Day 9: 6:00pm-7:00pm")