I had an idea that I had to wake up for and write... Im not saying it does not have flaws but I enjoyed it.
In the end Jacob ask each candidate if they still want to live on the island or if they want to go back to the way their lives would be if the island never existed. All of them choose to live the life of the alternate time line except two.
Then you see Frank sitting on the island as a ship comes up. HE says we have work to do brother... to someone off screen. Then Desmond comes up and says Im not your brother brother.
Bam! Lost title.