Before we get on our Game of Thrones soapbox and start spitting out secrets, we must warn you that there are HUGE spoilers in the following 3-4 paragraphs...so best not to read on if you enjoy the thrill of terrified surprise.
For all those who just want to know the damn secret, here goes.
Joseph Mawle (aka the actor who plays Benjen Stark), has just been credited by IMDB for appearing in the Sunday May 29 episode of GOT titled "Blood of my Blood" (huge thanks to Elite Daily who initially pointed this f*ck-up out).
As avid GOT fans may recall (and again, according to IMDB) Benjen hasn't appeared in the series since season one (you know, when he took Jon Snow to join the Night's Watch).
Although we all thought he was dead (hello, his horse galloped back to Castle Black's gates without him which is never a good sign), the next episode could be the perfect time for Benjen's shocking return (because who else is going to rescue Bran and Meera?!)