The game was designed to have you go to the lighthouse before going to the prison.
You have to climb the steps, a few at a time then ducking to avoid the strong wind. In the keeper's room, put the thermometer on the wall -- it will alert you when to come back to the lighthouse a second time. Use the lighthouse beam to see the prison. Go there and then back to the beach at the Inn. You will be summoned back to the lighthouse. Follow the ghost upstairs (easy now) and hear his story. Use the beam of the light to see the wreckage in the bay to the north (above), then leave in the boat and travel there.
The first time you visit the lighthouse, you have to go up the stairs and duck the winds that regularly blow down them. In the Keeper's room, set the thermometer on the wall. After you use the searchlight to see the prison, leave and go there to complete the quest involving the warden's and prisoner's ghosts. Then when you return to the beach at the Inn, you will get a signal from the thermometer to go back to the lighthouse a second time.
From the outside, you can look at the prison when you are there the first time. The second time, when you talk to the Keeper's ghost, you can use the light to see the rocks where the ship wrecked, dooming the keeper to spend eternity in the lighthouse (he is relased at the end of the island quest).
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On your first visit, put the thermometer on the wall -- it will alert you when to come back to the lighthouse a second time. Once you go to the prison and back to the beach at the Inn, you will be summoned back to the lighthouse. Follow the ghost upstairs, easily now, and hear his story. Use the beam of the light to see the wreckage in the bay to the north (above), then leave in the boat and travel there to search the rocks.
At the upper left, above the lighthouse. You can only search the reef after you talk to the ghost lighthouse keeper and use the searchlight.
To the shipwreck near the lighthouse.
There are 5 that you will encounter, and they are all connected to the same story. -- The Woman in the Window (haunted house) -- The Cemetery Specter (the cemetery) -- The Tireless Thief (the bank) -- The Warden's Sweet Tooth (island prison) -- The Restless Lighthouse Keeper (lighthouse) (see the related question)
She is in the lighthouse.
go to the lighthouse.
At the shipwreck north of the rocks in the harbor. After your first visit to the Lighthouse, and to the prison, you will be summoned back to the lighthouse to see the Keeper. The lighthouse light will show the wrecked ship on the rocks. Leave the lighthouse and go there in the ship, and you will get the locket to return to Fiona.
Nothing. It has nothing to do with solving the mystery on Ghost Story Island. The four ghost-hunter devices are: thermal scanner - sees the "tireless thief" beneath the bank vault floor thermometer - detects the lighthouse keeper EMF detector - finds the warden's office camera - takes pictures (can it photograph a ghost?)
Once you have gone to the Inn, and used the violin to enter the haunted house on the hill, you can see the Lighthouse with the telescope there. You will then get your ghost-detecting equipment from Jane at the Gingerbread House. Your first task is to get a photo of the Cemetery Specter (lot A at the cemetery). Once you sell this to the editor of the Herald, and deposit your money at the Bank, a small boat will dock on the beach and you can travel to the Lighthouse and the Prison island. When you return from your investigations, you will be prompted to go back to the Lighthouse to find the Keeper.
go to the lighthouse but watch out for wind!
On your first visit, climb the windy stairs and leave you Thermometer (it flashes) in the Keeper's Room. Then go do the prison if you haven't already, and return to the beach at the Inn. You will get a signal from the thermometer to go back to the lighthouse.
You go inside of it and you cant get knocked down by the wind.
As best as can be determined, the original plan for the quest was to have you go to the lighthouse first when you get the boat (Kestrel). Then you would see the prison with the lighthouse searchlight, and go to the prison after setting up the thermometer in the lighthouse room. Then, when the prison was done, you would return to the beach (by the inn) and there get the message to return to the lighthouse. The lighthouse keeper and the locket from the wreck let you continue.