Stranger in a Strange Land - Skellige
Location: Kaer Muire
Quest Giver: Automatically accepted upon completing Contract: The Phantom of Eldberg
Other Requirements: This quest must be completed before you finish King's Gambit
The Stranger in a Strange Land quest begins immediately upon completing the Contract: The Phantom of Eldberg quest; unless you have completed or failed the King's Gambit Quest. Completing or failing King's Gambit makes this quest as well as The Cave of Dreams Quest unavailable.
First thing you will need to do for this quest is to escape the prison. Attempt to speak with the guards first to push the quest forward then you'll be allowed to choose one of the other methods of escaping. There are multiple ways for you to do this, however I recommend speaking to Simun Brambling whom is the only prisoner in here with a name and accept his help. This will lead to a future quest by the name of An Unpaid Debt.
Alternatively if you don't care about doing that quest, use Axii on the guards or beat up all four of the other prisoners and this will progress the quest forward the same way.
You'll have some more dialogue in the jarl's room but no matter what options you choose the quest will end with you agreeing to help the jarl's son, Blueboy Lugos. This will begin the next quest in the chain, The Cave of Dreams.