Sam and Dean devise a plan that will save innocent lives. Meanwhile, Jack continues to wrestle with the consequences of his decisions.

Jack, Greer, Wright, Alena and Luka all work in concert to prevent the start of a third world war.

In Moscow, Jack teams with Luka to expose the high-ranking cabal members within the government who are now orchestrating the secret Sokol plan.

Jack races to stop the detonation of the Sokol nuclear device, which has traveled to the Czech Republic. Petr and Luka’s secret histories come to the surface in a deadly reckoning.

Jack and Mike head to a mysterious, abandoned outpost in Russia to seize the Sokol nuclear device, but an unexpected visitor foils their plans. Meanwhile, Petr seeks to rescue Alena, who has been kidnapped by her own head of security.

In Budapest, Jack and Mike plan a sting on a slippery arms dealer to ascertain the whereabouts of the Sokol nuclear device, as Greer discovers some intriguing and potentially incriminating information on Petr Kovac.

Sam, Dean, Castiel and Gabriel must work together if they have any hope of bringing Mary and Jack home. Meanwhile, Rowena’s encounter with Lucifer may alter the outcome of the journey for one of our heroes.

Jack travels to Vienna to track down the source of his original intelligence on Sokol. Greer advises Alena on a key NATO deal. Petr Kovac, Alena’s father, hosts a hunt in the Czech woods.

Kirk investigates a series of grisly murders on a mining planet that are the work of a seemingly hostile alien creature.

Jack, out in the cold and on the run after the fallout from his failed operation in Greece, must evade authorities both foreign and domestic before receiving help from an old friend.