Most of this game involves walking around the large house and triggering nightmares (the house will go blue, and you need to find an object that can hold your reflection to start the nightmare). There are 3 nightmares in total, each of which can be viewed through 2 different perspectives. You are given the opportunity to jump between the 2 people involved in the nightmare near the beginning of each, but it makes more sense if you don't take this option.
The manual for the game mentions "reading" objects, by holding the mouse button down and moving the mouse over the object - this same term will be used in the walkthrough below.
Start the game by using the knocker on the front door and entering the house. Go through to see your Uncle Edwin in the studio, painting. Talk to him, then look at the picture on the floor. Next take the glass of black thinner from the table next to Uncle Edwin, then use it to give it back to him. Turn away, then turn back to your Uncle and he tells you that your brother Henry is here. Leave the studio and go up the stairs. Enter the room straight ahead, which is the conservatory. Approach your brother Henry, then turn to Elise - she will talk to you, then the house will go blue. Walk towards the windows, then turn around, look down at the table, and read the wine bottle.
Cask of Amontillado - Montresor
Turn left from the window and proceed towards the bridge. Talk to your servant and you will give him orders to leave. Look toward the bridge and read Fortunato . You can do this in 2 different places before actually reaching the bridge. Step forward on to the bridge and approach the people on the other side. When you hear a lady laugh, turn to the left and a bald man will speak. Turn right twice and click on the lady in gold. Turn right and walk torward the street, then turn right and speak to Fortunato. Turn left and speak to his friend, then right to Fortunato again. Turn left and walk down to the street, then turn around and talk to Fortunato again - you will go to the vault. Go forward through the gate, then turn right to the vaults. Open the door and go through, then take the torch before turning right and entering the maze. Proceed through the maze, stopping to give Fortunato a bottle of wine from the two shelvse you pass. You will eventually reach a large cavern where you can place your torch in the holder on the wall. Turn right and Fortunato will walk forward into a small grotto. Follow him inside, then pull the chain to the left across to the right to trap him. Look away and you will step outside the grotto. Turn to your left and move some bones out of the pile to reveal a brick. Turn back to the grotto and place the brick on the wall. Keep building the wall in between automatically talking to Fortunato. When the wall is finished, turn and walk away.
Leave the conservatory and head back downstairs and into the studio. Look at the new painting on the floor and Uncle Edwin will come up behind you. Turn to him and he will leave. Go behind the easel and look at it, then head out of the studio into Edwin's office (the doorway to the left). Go to the desk and look at the mind map and the letter from Henry, then leave this room and go upstairs. Turn right and go through the door on the right (Henry's bedroom). Speak to Henry until he leaves, then pick up the note from the window before wandering the house. In particular, make sure you visit the gallery on the ground floor. Keep returning to the base of the stairs, until you witness Henry calling up the stairs to speak to Uncle Edwin - this will trigger the house going blue again. Go up the stairs into the conservatory again, and this time read the wine glass.
Cask of Amontillado - Fortunato
Look up from the water and read the man standing on the shore across the water. Turn left and read your friend , then click on him. Turn around and approach the bald man, then read him . Turn right to the lady with the purple mask, then turn and approach the lady in gold and read her . Turn away from her, then turn back and read her again . Walk further back along the bridge and approach the lady with the purple mask again. Turn left and point at the man across the water. Turn left again and walk towards your friend. Turn left and approach the lady in gold, then turn right and walk down to the street. Turn right and go forward, then turn left to see a beggar. Click on him, then turn right to meet Montresor. Turn away, then toward him, away, and toward him again, then click on him to go to the vault. Walk forward several times to enter the vault, then turn left and grab the torch. Turn right again and proceed. Read the skeleton on the floor, then take the stairs to the right. Read the feet in an alcove, then proceed to the left. You will eventually find a spiral symbol on the wall - turn to look at Montresor at this stage. Turn right a few more times, then go forward into a large cavern. Put your torch in the holder on the wall when prompted. Turn right and enter the grotto with the wine bottle. Turn around to see Montresor behind you. Turn away, then toward him repeatedly until the wall is finally built. Now read the wall , read the wine bottle to the right, and read the skeleton to the left. Turn back to the wall to end the nightmare.
Once again, leave the conservatory and go down into the studio. Speak to Uncle Edwin, then look at the new painting on the floor, then turn to Edwin again. Go up the stairs and knock on the door of the conservatory, then go inside and talk to Elise. Take her note, then read the piano until Elise gasps. Turn to her to see she is bleeding, and the house will go blue. Go down the stairs and into Edwin's study. Look at the desk and read the knife.
Berenice - Egaeus
Look down at the desk and pick up the pen to start writing the letter. Look away and open the middle drawer, then read the pendant that you see. Turn right twice and read the portrait of Berenice with a red vest. Turn right and walk forward once to the fireplace, then turn left and read the portrait of your father. Look down and read the fire. Turn right and approach the corner of the room, then look down and read the Poynton family history. Turn right and go across to another corner of the room, reading the top left of the 3 paintings. Turn right and move forward, then turn left and read the window. Return to the desk and pick up the pen, then finish the letter. When you near a knock on the door, look up and Berenice will enter. Read the images floating around her, then click on her to propose. After she has gone, turn around and read the fan on the table next to the armchair. Next read the desert painting from the group of 3, then read the window again. Turn around and you will see many visions of Berenice. Go forward to see a flickering image of yourself in the armchair, then turn again and approach the group of 3 paintings - all will show Berenice. Go and look out the window next to the desk. Approach the desk and look at the new letter. Turn around and read the red vest portrait twice. Go to the middle of the room and look at the door - Berenice will enter. Read her teeth. Now look at the teeth in the fireplace portrait, read the red vest portrait, read the portrait with the severed head, then the bust right next to it. Look out the window near the desk again. Now go over and open the door, and the maid will tell you Berenice is no more. Back at your desk, look at the book, try to pick up the box, and look at the book again. When you hear a knock on the door, look up and the maid will enter. Click on your bloodied hand 3 times, then turn left and approach the fireplace to see a spade. Turn back to your desk and take the box.
Look at the new paintings in your Uncle's studio and in the gallery, then go up to the conservatory and take the note from the piano (even if you are sure you picked it up before, it will be there). Next go to Henry's bedroom and you will give him the note. Turn away, then turn back to him again and he asks for your help. At the knock on the door, turn around to see the servant, then leave this room and enter Elise's bedroom next door. Go towards your Uncle and read him, then turn away and he will ask you to get the lantern. Go down to his studio (not the study) and get the lantern from next to the easel, and return it to the bedroom. Turn to leave and the house will go blue. Now go down to the study and read the bird cage.
Berenice - Berenice
Look down at the drawer and open it. Get the note from the back of the drawer, then return it again and close the drawer. Turn around and go to the chest at the end of the bed - open it and read the wedding dress. Close the trunk again, and approach the writing desk. Take the book, and read the flower that is revealed. Pick up the photograph and return it again. Look at the letter, then pick up the pen and sign the letter. Finally, pick up your medicine and go towards the door. When you reach the door, turn left and walk to the bed - you will hear a knock. Turn back to the door to see your maid. Now head out of your room, down the stairs, and to the right. Knock on the door, then enter. Approach Egaeus and read him, then he will propose. Click on him and you will faint and awaken in your room. Go to the desk and finish the letter, then go to the dresser and look in the mirror. Approach the door and you will hear a knock. Walk back into the middle of the room and face the door, and your maid will appear. Once again, leave your room, go down the stairs and right. Open the door and approach Egaeus, then turn away and leave. Return to your room and get your medicine. When you awaken, pound on the inside of the casket until it is opened.
Go to Elise's bedroom and take the lantern from your Uncle. Walk down the stairs all the way to the basement, and then follow the passages to reach the vault. After the coffin is placed on the trestles, put the lantern on the shelf to the right. Turn around and follow Uncle Edwin out of the vault and the house will go blue. Head back up the stairs to the ground floor and go left past the gallery, then take the first door on the right and read the cleaver.
Tell-Tale Heart - Young Man
Look around the room, then sit down in the chair near the table and pick up the newspaper. Leave this room and enter the first doorway on the right, which is your room. Go to the desk and pick up the chalk, using it 3 times on the piece of paper to make a sketch. Look at the desk again and open the drawer on the right, then read the glasses before closing the drawer again. Leave this room and return to the kitchen, and approach the far window. Turn around and read the old man. Approach him and read him again, then go back to the window and he will say it is late. Turn around and he will go to bed. Walk to the clock straight ahead and read it to wait until midnight. Go down the hallway and turn to the lantern on the shelf to the left. Slide the dimmer over to the right then pick it up. Open the door at the end of the hall and enter the room. Slide the dimmer open and you will see the eye is closed. Leave the room and go all the way to the window in the kitchen so another day will pass. Turn around and the old man will leave again - this time when you look at the clock it will already say it is midnight. Go down the hallway and pick up the lantern, and enter the old man's room. He will stir this time - carefully approach and open the dimmer, then walk towards him until you kill him. Back in the kitchen, go and pick up the saw that is hanging on the wall next to the stove. Head back to the old man's room, approach the end of the bed and look down to see bags of body parts. Pick up one of the bags, then turn right and pull up 2 floorboards. Place the bag in the hole. Place the other 2 bags in the hole, then replace the floorboards. Leave this room and you will hear a knock on a door. Go out to the kitchen and open the door right of the window to be greeted by 3 policemen. Turn right and they will come inside. Turn to face them again and they will start to search. Go back to the old man's room and they will follow you there. Once they have entered, read the man in the doorway. Turn right to see the fat policeman, then turn right to see the the blonde policeman, who will search the chest of drawers. Now turn left and right between the cops until you can click on the fat policeman's face to confess to the murder.
Look at the paintings in the gallery and the studio (floor and easel), then go upstairs. Head left, and enter the first door on your right to find Henry in an open-air room. Talk to Henry, then read him. Go back downstairs and you will meet Uncle Edwin coming out of the gallery. Follow him to his study, where he offers you a letter. Take it and read it, then go upstairs and give it to Henry. Turn around and go downstairs and out the front door, then after the scene outside, turn around to see your Uncle once more. The house will go blue again. At this point, you can head up to the open-air room and walk out into the air to hear a recital of Annabel Lee. Now head back to where you found the cleaver, and this time read the fish .
Tell-Tale Heart - Old Man
Turn left from the mirror and approach the window to see a blonde policeman outside. Turn around and read the clock face to see that it is quite late. Next approach the table and read the newspaper, then get up and go left to the stove. Look left and get a bowl, then look right and get some soup. Sit down at the table again and pick up the spoon, then click on the soup several times to eat some of it. Leave the kitchen and go through the door at the end of the hall to enter your bedroom. Go to the chest of drawers and open the top right drawer. Pick up the coins and read them, then also pick up the brochure and the wedding ring. Turn around and pick up the book from the desk and the portrait from the bookshelf. Leave this room and go back to the kitchen, and the young man should be there. Sit down and eat some more soup, then get up, turn around and look at the clock - you will comment that it is late. Go back to your room, put out the candle on the desk, and get into bed. When you are awoken, read the portrait, then the doorway, then the intruder. Click on the light.
You will be standing in front of the Red Death tapestry. Turn around and go through the door, then keep walking and opening doors to progress through scenes from the nightmares you have just experienced. You will eventually reach a brick wall. Take the pickaxe and use it repeatedly to knock the wall down. Go through to find Elise and finish the game.