Everyone is wondering "want made hurley return to the island and what's with the guitar case" well there are a few thoughts I have on that.
1- Hurley talks to the dead and we just saw faraday died in 77 could Hurley have been talking to faraday for along time. Faraday could have visited hurley in jail and said something to convince hurley to return and also told him to bring what's in the guitars case. Also faraday could have traveled forward in time from when he worked at oxford or during the three years he was off island being guided by his mother to visit hurley in jail. Hurley would of course think faraday is dead and faraday would have to act like he knows Hugo if he traveled from oxford. Then convince him. 2-hurley as we know talks to the dead like I previously said and who just died before they returned to the island........John Locke. Possible John went to see hurley although this time John succeeds in convincing Hugo to return to the island with the guitar case.