The Sons of Anarchy actor will appear in two episodes in the third season as Quarles (Neal McDonough)'s boss and head of the Detroit Mafia.
He will feature in episode 11 and the season finale.
Show creator Graham Yost told Entertainment Weekly: "There is a physical tweak that Adam asked for. Adam wanted to be distinctive, so when you see it, it's like, 'Oh wow, that's pretty wild'.
"He's not dressed as a pirate or anything. But he looks cool."
In the most recent episode 'The Man Behind the Curtain', Theo's son Sammy (Max Perlich) was introduced with Theo referenced by various characters.
Arkin has previously directed five episodes of Justified including 'Thick as Mud'.
Justified continues on Tuesdays at 10pm on FX.
> Read Digital Spy's recap of 'The Man Behind the Curtain'
Watch a promo for the episode 'Watching the Detectives' below: