After helping to thwart Hydra, Agent Phil Coulson was appointed as Director and tasked with rebuilding the agency. Agent Melinda May, expert pilot, martial artist and longtime friend, will continue to look after Coulson in the wake of the mysterious etchings he's been carving into walls. Grant Ward, highly trained in combat and espionage, was found to be a Hydra mole and a traitor to S.H.I.E.L.D. and locked up away from the world and his former teammates. But this isn't the last we've seen of him... After being left to die in the middle of the ocean by Ward, Agent Leo Fitz, brilliant engineer, and Agent Jemma Simmons, genius bio-chemist, found a way to escape their watery grave. But all did not go well for Fitz, who was left in a coma and may never regain his full cognitive functions; a devastating blow to Simmons. And computer hacker Skye, now a full-fledged S.H.I.E.L.D. agent, discovered her origins as a 0-8-4 — an object of unknown origin — and that her parents were considered "monsters." Could Skye have darkness lying dormant inside of her? Also joining Coulson's core team is Lance Hunter, a dashing mercenary sharp shooter with a quick wit. Since he didn't rise up through the ranks, does he have an ulterior motive for helping out the team.
So we know that in this week's episode "...Ye Who Enter Here" Coulson and his team will find the city before HYDRA, but while Mac, FitzSimmons, Coulson, Morse are in the city Skye and Koenig are in other mission, Get Raina before Whitehall.
While Skye tries to get Raina out of a S.H.I.E.L.D. safe place (As we saw in the clip) they are all attacked by who seems to be Melinda May with half face ripped off, but the question still remains is that really an alien or Agent May?
I think many people know the answer by now, but the answer is no.
Who is she then?
Agent 33 with the mask she used in Season 2, Episode 4.
Why does she look like Agent May?
When Agent 33 was going to use an electric wire to kill Agent May, she manages to use the attack of Agent 33 and use it against her leaving half of her face burnt due to the electric shock. I think the electric shock gave the mask a "glitch" leaving it permanently attached to her face.
As we see in the image above we see Agent 33 seriously hurt after her fight with Agent May, this picture is also a proof that the "May" we see in Episode 9 is Agent 33. Look at her face, it is the same part of the face which was electrocuted. I honestly don't have any theory regarding on why she is still after S.H.I.E.L.D. I believed she was dead, but if she wasn't I at least thought the brainwash by HYDRA would be lost.
P.D: I'm learning english as it is not my natal language, any mistake (I'm sure I have plenty) post it on the comments. The Feedback will be very helpful.
Enjoy tonight's episode!