Superficially, the title refers to the two new Valyrian steel blades that will be forged from House Stark's old greatsword, Ice, which we last saw being used by the royal executioner Ser Ilyn to behead Ned Stark way back in Season 1.
But of course, all of these episode titles have deeper meanings…
With this week's episode, Agents of S.H.I.E.L.D. is starting to feel like a Joss Whedon series again. The dialogue still isn't there, but the story arc is.