Hydra is preparing a sacrifice for Agents of SHIELD's midseason finale, a blood offering that just so happens to go by the name Leo Fitz.

'Agents Of SHIELD' Season 3: Explosive, 'Game-Changing' Midseason Finale Brings Absolute Terror, Clark Gregg Weighs In

Fitz (Iain de Caestecker) and Simmons (Elizabeth Henstridge) dug into the history of NASA's Distant Star Pathfinder only to discover that it's ram's head insignia not only marked it's victims as a form of sacrifice, but also placed the portal program under Hydra's auspices.

Now that Malick (Powers Boothe) has managed to shanghai Fitz to Maveth, the scientist may suffer the same fate as Will's companions. It's a plan the conniving leader shares so jauntily with Simmons in a heart-stopping sneak peek for "Maveth."

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Oh, FitzSimmons. You both really are cursed, together and apart.

While Coulson (Clark Gregg), Ward (Brett Dalton), and Fitz take on the exiled Inhuman, Mack (Henry Simmons) will be forced to lead the rest of SHIELD into a battle to take the Hydra castle, rescue the Inhuman army Malick is trucking in, and pull their men back through the portal. It certainly sounds like an impossible mission, and the fallout will be earth shattering.

"I would say that this midseason finale has two shocking twists and both of them are bigger than anything that happened in last season's midseason finale," Gregg told Entertainment Weekly, indicating that the "Maveth" revelations will dwarf Daisy's (Chloe Bennet) terragenesis and Tripp's (BJ Britt) untimely death.

Catch all the action this Tuesday at 9 p.m. ET on ABC.