Frank has a fairly grizzled appearance, mainly a habit he developed when he was required to work short term undercover assignments. He only ever rough shaves, leaving a little stubble. He has had his nose broken a few times while working as a cop, so that it now has a slight tell-tale kink in the bridge. A very faint scar on his left cheek is a souvenir from his youth, when a guy in a bar once came at him with a broken bottle, after his older brother, David, started a fight. He is leanly and athletically built, a testament to years of tough police work.

Frank tends to vary the way he dresses to suit the environment he is in, another throwback to his undercover work. When not on assignment, he tends to dress semi-smartly, with a shirt and jacket on top of chinos or jeans. He favours smart ankle-boots over shoes, and dislikes wearing ties.