“The Writing on the Wall” is episode seven of season two of Marvel’s Agents of S.H.I.E.L.D.
At the end of the previous episode, “A Fractured House”, Grant Ward had escaped from custody as he was being transferred to his elder brother, the senator. I had wondered if that had been a setup, and if S.H.I.E.L.D. had expected him to escape, but apparently not, as May and a team are searching for him.
A woman is killed in New York state by the man we had seen getting tattoos of the strange symbols tattooed on him (that’s what the title of this episode relates to, the, apparently alien, symbols that Coulson had been carving on the wall). The woman has the same symbols carved into her flesh. It turns out that both she and her attacker also had the alien blood, GHD 50, in them, and Coulson recognises the woman as a S.H.I.E.L.D. agent.
Because Coulson’s memory of the time he managed the T.A.H.I.T.I. project have been changed, he decides to use the machine that Raina was using on him in “The Magical Place” to try and recover them.
Kind of unclear whose side Ward is actually on these days.