Falling Skies’ season 3 rains down its 9th and penultimate episode of the year with “Journey to Xibalba,” where Tom Mason returns to base as an explosion in Charleston traps hundreds of survivors underground, and the identity of the mole finally comes to light.

Previous ‘Falling Skies’ episode “Strange Brew” saw Tom Mason suddenly back in his old life as part of Karen's elaborate deception to extract information, so what does the latest episode bring?

Read on for your in-depth recap of everything you need to know about ‘Falling Skies’’ season 3 penultimate episode, “Journey to Xibalba”!

As Weaver keeps Marina up to date on the status of the Volm weapon’s deployment, Lyle notices a sailboat approaching on the horizon. Pope heads down to the shore to see Tom Mason returning once more, shortly thereafter greeted by the rest of Charleston. Tom finds his children to explain what happened to Anne and Alexis, ultimately giving in to his hate and swearing they’ll get revenge on Karen for all that she’s done.

Tom advises Weaver and Porter to make their target Boston in order to both bring down the grid and take out the Northeast’s leader, but both men note that Tom could use rest, and may well be bugged, considering the increased risk of attacking Boston. On his way out, Tom encounters Cochise alive once more, and the pair share their worries about emotions clouding their judgement. Tom next pays a visit to Pope to ensure that he’ll be put down if in fact he has a bug, but all of Charleston is soon rocked by a massive explosion.

In the aftermath of the blast, Tom and Pope see that the entire Volm complex has been destroyed, and Cochise seriously injured. He and Pope carry the body to the infirmary, dragging along a suspiciously flighty Lourdes, though Cochise assures them his body will heal if left alone for long enough. On her way out, Lourdes plants an alien bomb in one of the vents, and nearly gets caught by Weaver in the process.

Hal finds Maggie in the armory, as Maggie assures him they’ll get vengeance on Karen, before Lourdes’ bomb goes off and sparks several cave-ins around the complex. Tom finds Marina alive, but with damaged vision, as Hal finds a similarly stunned Maggie in their enclosure. Meanwhile, Ben leads the survivors above ground in digging toward the trapped residents. Tom finds Lourdes in the rubble and carries her to the infirmary, as the on-call doctor deems her injuries minimal and places her to the side…next to Cochise.

Tom and Anthony search for an unblocked exit to the facility, instead finding a surviving Dr. Kadar, while a trapped Hal and Maggie realize they might soon run out of oxygen, and begin arguing about Hal’s last mission without her. Dr. Kadar proposes they can blast their way to the surface with a homemade bomb, while the other doctor urges Lourdes to stop moving. Tom consoles Lourdes over Anne’s death and their current situation, but recoils when she mentions that Anne died right back where they all started.

Still trapped, Hal worries that he might have planted the bomb before his bug was extracted, as the two console one another for the end. Meanwhile, Dr. Kadar worries about his bomb damaging a nearby support beam, and Tom has a sudden realization. Lourdes prepares to kill Cochise, before Tom interrupts them and brings her to tend to Anthony. Once there however, Anthony rolls over, and all train their guns on Lourdes, Tom having realized he never told Lourdes Anne died in Boston. Cornered, Lourdes pulls her weapon, but not before the others can subdue her.

Matt and Ben patrol the underground storm drains looking for signs of survivors, finally hearing Maggie bang on a pipe in their enclosure. Finding the source, Matt and Ben manage to make contact with a weakened Hal and Maggie through the pipe, and open the nozzle to allow oxygen into the room. Meanwhile, a bound Lourdes taunts Tom that his mistakes cost the lives of his loved ones, before Tom grabs her Volm weapon and blasts open the wall near Dr. Kadar’s bomb, finally providing a way out.

As the survivors slowly emerge from underground, Tom explains that Lourdes had been the true mole, relieving Hal, as he and Maggie agree to go after Karen together. Nearby the Volm complex, Tom finds a revived Cochise despondent over the loss of his comrades, and uncertain how they’ll manage to operate the surviving Volm weapon. Tom proposes that Dr. Kadar might be able to help, and they’ll continue the fight no matter what.

For as surprisingly emotional and resonant as last week's "Strange Brew" proved in moving away from the main storyline, the same can't exactly be said of "Journey to Xibalba." 'Falling Skies' understandably walks a line between more effects-heavy plot-driven episodes and those with more practical, human conflicts, but we have to question the decision to induce such a setback only one episode before the ultimate finale.

Further along those lines, we're given to understand that the entirety of the Volm have been eradicated offscreen save for Cochise, denying us any real payoff for the promise of last season's finale, which had so opened the 'Falling Skies' narrative to begin with. We'll certainly hope that next week's finale justifies such a non-start of an episode, but we might have appreciated more plot development than Lourdes exposure as the mole, going into the last hour of the season. Every principal and ancillary character survived, to boot!

Did you get your fill of Skitter-y ‘Falling Skies’ action? What did you think about tonight’s episode? Join the discussion in the comments, and be sure to check back next week for another recap when ‘Falling Skies’ returns with season 3 finale “Brazil” on TNT!

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