After the captain of the guards forgets his sword, you follow him to the Sanctuary to return it.
Meet Seres and Dampé
In front of the Sanctuary, you find Seres talking to Dampé. When you explain that the captain forgot his sword, Seres goes inside to tell her father the priest, who is talking to the captain.
Suddenly you hear Seres cry out, then the Sanctuary doors lock. Dampé doesn't have a key, but he has heard that there is a secret passageway under one of the graves in the graveyard. He recommends that you use the sword if you're in trouble. You can choose whichever dialog you want, but you should agree to use the sword, because you kind of have no choice. You can swing it by pressing B.
Find the Secret Passageway
Go east into the graveyard.There are some green Buzz Blobs walking around. Just hit them with your sword to get rid of them.
You can push up the graves by standing in front of them, then pressing A to hold them, then push up. Some of the graves have rupees underneath, but beware: Poe ghosts might pop out of some of the graves and attack you.
The hidden passage is under the grave that is surrounded by walls. Cut the trees south of this grave in order to reach it. Hold the grave with A, then press up to push it up. Then go down the stairs to enter the secret passageway.
Reach the Sanctuary
Go north. There are some pots blocking your path, so swing your sword to get rid of them, or press A to pick them up and throw them. Then keep going north to find a glowing chest. Press A to open it. You get the lamp! The touch screen will guide you through equipping it. Tap Items, then drag the lamp to the Y button area. Then you can press B or tap Close to close the items menu.
You don't have to press Y to make the lamp provide light. It will light up the dark areas wherever you walk. You can press Y to make a temporary flame in front of you.
Go north into the shallow pool of water and read the tablet for a clue about what to do next. Go north to find a locked door. Use the lamp on the two torches to the left and right of the door to make it open.
You can use the lamp on the torches here, but they only stay lit up temporarily. Be careful of Rats and Ropes in this room.
Go west from the door to find a chest. Open it to get a red rupee.
Go west from there until you can't go any farther west, then go north to find some stairs. They lead to a door, but it's locked. Go east from the locked door to walk on a raised path. You'll see a rupee to the north. Continue along the raised path to find another chest. This one contains a key.
Go back to the locked door to the west and press A while standing in front of it. You'll unlock the door and go through.
Once you are in the room, the door will lock. There are three Poes floating around the room. Defeat them all to make the north door open. Go through.
In the next room, there are two switches in the north wall. You have to pull the correct one to make the door open. If you pull the wrong one, Ropes will fall from the ceiling and attack you. The correct switch is on the left. Pull it to unlock the door. Go through.
Enter the Sanctuary
You are now in the Sanctuary. Go west and then walk north. In a cutscene, you encounter a bad guy named Yuga, who turns Seres into a painting, then defeats you and threatens to turn other things in your world into paintings. The priest says you must warn Princess Zelda.
Afterward, you wake up once more in your house. Ravio is there. He's a travelling merchant. He found you in the Sanctuary and dragged you back here. You tell Ravio what happened and he tells you to report it to the castle immediately. But before you go, Ravio asks if he can stay in your house for a while. You can choose whatever dialogue you wish, but eventually you have to agree to let him stay. Ravio gives you his bracelet as payment for letting him stay.
Go outside and save at the weather vane. Then go north to the castle.
Go north into the castle courtyard and talk to the guard at the main door. You go into the castle with Impa.
Inside, Impa encourages you to take a close look at the painting gallery. Start on the far left side. Each painting tells a part of the history of Hyrule. The guard to the left of the paintings says that Impa is a descendant of the Seven Sages. After you have looked at all five paintings, Impa comes out and says Zelda is ready to see you. Use the stairs to reach the door that she went into.
Zelda has had the same dream as the one that you saw at the start of the game, so she recognizes you. You tell Zelda what happened, and she fears that evil is rising again in Hyrule. Impa tells you to ask Sahasrahla for help, and Zelda marks his location in Kakariko Village.
Zelda also entrusts a charm of the royal family to you. It's a green pendant.
Explore the Castle
Before you go to Kakariko, there are a couple of things you can find around the castle. First, go south from the throne room, then east. From there, go south to exit. Go south after that, then west. There is a chest here that contains a purple rupee.
If you go down to the main courtyard where soldiers are practicing against scarecrows, you can use the northwest door and go to the north end of the room to get 5 rupees.
Go west from the castle to reach Kakariko Village.