Marvel has unveiled an extended trailer for the Agents of S.H.I.E.L.D. Season 6 finale, which was first unveiled during the long-running series' first Hall H presentation at Comic-Con International in San Diego.

The trailer teases an explosive conclusion to Agents of S.H.I.E.L.D.'s penultimate season, with the conflict between the agents and Phil Coulson's doppelganger, Sarge, coming to a head. Melinda appears dead-set on finding out if the old Phil is in their somewhere, while Sarge's power only seems to grow.

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Meanwhile, the show's heroes prepare for yet another battle with "fate of the world"-level stakes as the villainous Izel puts her endgame into motion. At the same time, the team continues to come to terms with Coulson's death, and heated debates ensue regarding whether or not a part of their former leader still exists within Sarge. The trailer ends on a cliffhanger of Daisy preparing, yet hesitating to strike Sarge with a sword. All the doppelganger has to say is "do it."

Marvel's Agents of S.H.I.E.L.D. airs Fridays at 8 pm ET/PT on ABC. The series stars Ming-Na Wen, Chloe Bennet, Henry Simmons, Iain De Caestecker, Natalia Cordova-Buckley, Elizabeth Henstridge and Clark Gregg.

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