Keyholes are located on most doors encountered in Dishonored and are used by Corvo Attano to scan a room before entering and to eavesdrop on any conversations going on inside. This allows Corvo to gain a tactical advantage over enemies, as he will know their positions prior to engaging or avoiding them.
This technique is made almost obsolete by Dark Vision, as that allows Corvo to see all enemies and (at Tier II) objects within a certain radius. This means that enemies can be seen through walls and doors, nullifying the need to peer through keyholes. However, Corvo must still use keyholes to eavesdrop on conversations, even with Dark Vision.
Keyholes are most useful when attempting to unlock Mostly Flesh and Steel.
- The best way to see Granny Rags talk to her 'little birdies' is by looking through the keyhole of her house leading to the backyard.
- Corvo can occasionally observe members of the City Watch or Overseers peeping through keyholes.
- Sometimes this will happen while Corvo is looking through a keyhole, but he will remain undetected.
- Some scripted scenes can be activated by looking through keyholes.