Sheriff of Nottingham: Merry Men contains five modules that can be added to the base game; as well as the option of including a sixth player. The five modules are:

Deputies: In six player games; you may use two Deputies instead of a single Sheriff. Here; both deputies must decide to search bags or let people pass; and they will share the punishments and rewards. If a deputy disagrees with the other and searches a bag; they will receive the punishment or reward by themselves.
Merry Men: Adds new illegal goods in the form of 'merry men' characters. If they are successfully smuggled in; players will reveal it and activate its special ability.
Black Market: Adds three sets of bonus cards that display illegal goods. The first player who successfully smuggles in the indicated goods receives the bonus cards and a large reward.
Laws: Sheriffs must draw three law cards and choose two to keep. The chosen laws are in play for the entire round.
Special Orders: Special order cards indicate combinations of one legal and one illegal good. If players can smuggle both of those items in the same bag; they get that card; which provides them with bonus gold.