Watch Sin City Full Movie Free Online 123Movies. Welcome to Sin City. This town beckons to the tough, the corrupt, the brokenhearted. Some call it dark… Hard-boiled. Then there are those who call it home — Crooked cops, sexy dames, desperate vigilantes. Some are seeking revenge, others lust after redemption, and then there are those hoping for a little of both. A universe of unlikely and reluctant heroes still trying to do the right thing in a city that refuses to care.