Breaking into Doctor Galvani's House | Mission 2 - High Overseer Campbell Dishonored Guide
Last update: 11 May 2016
The building that doctor Galvani lives in is located on the square between the two walls of light, so it won't be long before you find it. The most obvious way of entering the house is through the main entrance, but in this situation, you would start on the ground floor and you would have to make your way through to the second floor.
Another path you can take is to Blink (teleport) with the aim of reaching the balcony on either the first or the second floor of the building. This will allow you to go around the guards and Galvani;s servants on the lower floors. Regardless of which way of entering you choose, start the exploration of [Dr. Galvani's Office].
New Optional Quest: Search for a sample of infected rat viscera
The ground floor of the building is patrolled by guards. If you are patient enough, you can eliminate them one by one, but you need to remember to carry the corpses away to the area around the main entrance. Otherwise, I recommend that you go to the room to the left right away and collect (Galvani building key) on your way.
If possible explore thoroughly the entire ground floor. The items that you can find are: gold, food, crossbow bolts, two Sokolov's health elixirs, pistol ammo, three books and a log (Feeding Log). There are two ways of reaching the first floor - you can go up the stairs (the above screenshot), or use the Possession power to possess a rat and go through a damaged ventilation system screen.
The first floor of the building is initially occupied by a guard and a chambermaid. It is worthwhile to wait until they finish their conversation, because then, the guard should go to the second floor and leave the chambermaid exposed. Depending on what you like, you can either go around her, choke or kill her. You cannot, however, expect her not to react when she sees you, since she is Galvani's employee and would take you for a thief. It is worth noting that the chambermaid has a Galvani building key on her, i.e. the key that you can also obtain on the ground floor.
You can find further valuable items (some of them are hidden in cabinets that need to be broken) like gold, food, two books, two Pieroas spiritual remedies, pistol ammo, sleeping bolts and a safe (the above screeenshot). You can determine the safe combination by reading Galvani's log - it's 287. In the safe there are two bars of gold 100 coins each.
The second floor of the building is patrolled by a single guard, unless this is the floor that you started the exploration on, and you haven't yet witnessed the conversation of the guard with the chambermaid. Just like on the lower floor, you can go around the guard, choke him or kill him. The guard has a Galvani lab key on him. Some other valuable items can be found around like two spring razors and Cleaning Instructions for the chambermaid.
The secret room with the infected rat viscera in it, can be reached in two different ways. Variant one is about reaching the side room shown in the above screenshot and finding Piero's spiritual remedy on your way. While in the room, you need to Possess a rat and run into the nearby ventilation shaft.
Variant two is about reachimg the chamber from the main room on the second floor i.e. from [Dr. Galvani's Lab]. It is also worthwhile to explore the entire lab for food, gold, two books, a document (Galvani academy notice), Audiograph - Galvani's Speculation, Sokolov's health elixir and another Galvani lab key. To unlock the secret chamber, you need to pullone of the books (the above screenshot).
New Main Quest: Contaminate the Bottle Street Gang's Bootleg Elixir with plague
Regardless of the variant you choose, you will wind up in [Dr. Galvani's Secret Room]. Collect the book, gold, Piero's spiritual remedy and the plague rat viscera, after which you will receive further instructions. You may now leave the building. It is best to do that through the door in the main laboratory.