The Professional

The Professional is a perk

Effects
The Professional adds an additional 20% to extra damage granted by critical hits when using any pistols, revolvers, or submachine guns from either the Guns or Energy Weapons skills.

Behind the scenes
The Professional is a reference to the French movie Léon: The Professional.

Bugs

 * The portion of this perk meant to confine the bonus to apply only to sneak attack criticals is set up incorrectly: rather than checking if the target has detected the player, the perk mistakenly checks if the player has detected the player. Additionally, there is no check in place to ensure that the target has not been alerted without overt detection of the player, nor is there any check to ensure that the player is currently sneaking. Due to these issues, the perk applies to all critical hits the player inflicts.
 * Despite being one-handed revolvers, That Gun and Police pistol are not affected by this perk.