Keep dusting past the three obvious portraits — there are more than three.
Official in-game clue: "What else can you dust? There is more than three paintings."
Where: Day 1 Afternoon, in the hallway, during Preparing the Reception.
Why it gets missed
The hallway presents three portraits at eye level, you dust them, one falls, you reassemble it, and the chore is complete. The game has no reason to tell you there are others.
The clue is unusually explicit — there is more than three paintings is a direct correction of the assumption you just made. Take it literally and sweep the room for anything else hanging.
What to do
- Take the feather duster to every painting in the hallway, not just the three you were shown.
- Keep going after the first one falls.
- Reassemble what comes down.
Watch the animations while you dust
Every click on a portrait plays a short NPC animation. Those are not decoration — they are the clue for a password box later in the same day. If you clicked through them, you will be back here.
The chandelier in this room is a separate matter: it needs three candles collected across the afternoon's chores, and it gates the garden. If it will not light, you are short a candle rather than short an idea — see chandelier candles.
Nearby
The full list of hidden achievements, in the order you reach them, is on the triggers page. Going for everything in one run? See 100% completion.