A prisoner of Stannis and the Red Priestess, the last anyone saw of Gendry he was in a boat headed for Kings Landing after Davos Seaworth helped him make his escape. His arc in the book differs, and sees him stay with the Brotherhood Without Banners and not meeting Stannis or Melisandre, so if they were to return to the show theres every chance Gendry may well turn up with them again. Clearly, he'd have to get over the fact that they sold him. With nothing to suggest at this point that he has perished, and given his bloodline - being a bastard of Robert Baratheon and all - theres a chance he will still have more of a role to play before the end of the game. So you can perhaps expect him back. Joe Dempsie, the actor who plays him, tweeted last year that his character was still rowin'. Maybe hell eventually get somewhere, or otherwise - like Breaking Bads Huell on that couch - hell be stuck in that boat for eternity.