The Patriot Synopsis & Cast List

Here's the description for the SHIELD episode airing on the 17th. I wonder if this is the same secret Jemma threatened to reveal.

Coulson and Mack discover a shocking secret about Mace, which leaves all of S.H.I.E.L.D. in a dangerous position.

Guests: Jason O'Mara, Mallory Jansen, Adrian Pasdar, Maximilian Osinski, Patrick Cavanaugh, Troy Caylak, Kimberley Drummond, Shelly Robertson, Alastair Bayardo