Sinis is a talented thief, who was kidnapped during a plot by Ares to start a war between the Corinth and the Centaur Nation. He was watched more carefully by the slavers because be managed to slip his chains once, and was the first one to get free when Lilith, Iolaus, and Hercules arrived to rescue the centaurs. He set the other centaurs free, and in exchange Tyldus gave him his freedom when they returned to Corinth.
- Sinis had been Cheiron's pupil and would have made a fine warrior, but he'd chosen to become an outlaw instead.
- Sinis mentions having an appointment in Corinth to teach a boy named Autolycus how to pick locks.