Tania Louis is a Metro-Dade Detective, assigned to the Young Criminals Unit (YCU). Her specialty is that of data interpretation and high computer skills (akin to Velma in Scooby-Doo and Abby Sciuto--without the forensics--in NCIS) and does most of the inside investigation, using her skills to locate information on subjects of ongoing cases, she found out multiple details about professor Terrence "Terry" Baines to assist the team in their case. Louis works mostly with fellow detective Jack Andrews, but is intrigued by new arrival Joey Hardin. After Ray Mundy's death, Louis was ready to leave the group but Hardin and Andrews kept them together. After Baines' death, Louis, Andrews, and Hardin all continue to work together.