Go into the house to the left, Climb up the ladder and search for an Ether, climb back down and search in the bottom right corner to get 9693 Gil. Continue heading to the left, climb down the ladder that you come to and search in the top right corner of the platform to find a Red Hat. You cannot go any further, so climb back up the ladder and head back outside. Go into the house to the right this time. Continue moving to the right until you come to a rope, move to the right side of the platform and press X when the '!' appears. Follow the trail and enter through the opening, follow to the end of the path until you come to a chest, open it to find a Golden Hairpin.
Head back to the last area and climb down the rope. Do not touch the lever just yet, head to the right of the well, talk to Moolan the moogle to save your game and you should also have a letter from Mogrika to him. Moolan also has a letter for you to deliver to Mogtaka. Search the bottom right corner of this area for a Wing Edge, then proceed to the right. Move up the steps around the houses and head outside. Move down the walkway and search for Gaia Gear.
Attempt to go back to the well, you will encounter a couple of Red Dragons. They are not that hard, but they do a lot of attacks that target the whole party, such as Twister. You can cast Reis's Wind if they are dealing too much damage, cast Water on both of them with Vivi, Amarant and Zidane can just attack normally. If Amarant has Add Status support ability equipped as well as his Scissor Fangs, he has a chance of inflicting the Virus status effect on them. Continue your way back to the well, head to the left side of it this time.
Head into the house and search the bottom right for a chest, open it to find Demon's Mail. Exit this house and go through the opening next to it. Climb up the stairs and talk to Mogtaka, you probably have a letter from Moolan for him. Save your game and continue up the stairs. Head into the house to the right, another Red Dragon will attack you. Once it has been dealt with open the chest in this room to obtain an Elixir. Make your way back to the well, examine the lever on the right. Select the option to pull it down three times. Head towards the opening on the well and hop onto the rope, slide down to the bottom.
More Red Dragons will attack you, once they have been dealt with head through the newly created opening. Zorn and Thorn can be seen attempting to extract the Eidolons from Eiko. Watch the event and eventually a battle with Zorn and Thorn will begin. Eiko uses Terra Homing and completely owns Zorn and Thorn with one hit. Eiko receives the Mog's Ribbon, which allows her to summon the Madeen eidolon. Soon after, a boss battle begins.
This isn't a very difficult battle, Eiko will replace Vivi if you had him in your party. Start off the battle by casting Reis's Wind, then just continue attacking normally with Freya. Zidane can steal from Meltigemini, steal until you obtain the Demon's Vest. Amarant can throw his Wing Edges to deal a lot of damage. Eiko can cast Cura and other healing spells on the other characters.
Meltigemini likes to inflict status effects, Bio induces the Poison status effect. He also has an attack called Viral Smoke, which inflicts the Virus Status effect on the entire party, use Vaccines to remedy this. If one of your characters is still infected with the virus at the battle's end, they won't receive any AP, and Meltigemini gives a good amount of it.
Watch all of the events and dialogue that take place. You will eventually appear in Lindblum.