Archer’ season 4 goes under the sea for its thirteenth and final episode of the year “Sea Tunt: Part 2,” as the quest to stop the villainous Captain Murphy ('Mad Men's Jon Hamm) quickly falls apart, forcing Archer to make a deadly choice to save Lana's life.

Last week’s ‘Archer’ episode “Sea Tunt: Part 1” saw Cheryl’s brother Cecil (‘Bob’s Burgers’ Eugine Mirman) leading the ISIS crew on an expedition to recover a sunken hydrogen bomb, before the group quickly found he had more sinister motivations, so does “Sea Tunt: Part 2” suffer from decompression?  Is ‘Archer’ season 4 diving toward its deepest season yet?

Read on for your in-depth recap of everything you need to know about ‘Archer’ season 4 episode 13, season finale “Sea Tunt: Part 2!”

Captain Murphy continues to boast the launch of nerve gas missiles if his demands to save the ocean aren’t met, while the ISIS crew takes on the flimsy identities of a news crew tasked to interview the mad sea captain. Despite the fact that Murphy has never seen them, Archer and Cyril don fake mustaches, while Archer convinces Ray to shave his, if only to see how he looks without it.

After demanding to skipper and violently dropping the DSV in the ocean, Archer, Lana, Ray and Cyril begin their descent, while Malory, Pam and Cheryl scrounge the boat for any available alcohol. Lana bemoans how poorly put together their mission is, while deep down on the ocean floor we see Captain Murphy gleefully gloating about his plan to a crew of…no one.

When Archer and the others dock, Lana attempts to convince Captain Murphy to conduct their interview by the actual missiles, though Murphy insists on filming on the bridge. Meanwhile up top, Cecil explains to the others that his entire half of the family fortune had been lost in his philanthropy, with $200 million alone going into the SeaLab facility, hence his attempt to take Cheryl’s half.

Back in the lab, Captain Murphy laughs about the money sunk into both the facility and his salary, but when Lana points out the insanity of his demands for a worldwide fishing moratorium, she soon realizes that Murphy doesn’t have any missiles after all. Murphy admits that the foundation went broke and the crew abandoned the facility, leaving him alone for the better part of two years. Murphy makes one last power grab to hold a knife to Lana’s throat, to which Archer produces his gun, but Murphy insists a gunshot in the lab would kill them all, and drops his knife. Thanks to one of Krieger’s safety modifications, the gun fires anyway, producing a small crack that soon widens, and gushes water into the lab.

With water rapidly filling the room, Murphy leads the four to a nearby safety hatch, jettisoning them into the adjacent break room. Murphy attempts to seal the hatch behind him, but is instead sent flying into a wall, and crushed by one of the vending machines. With his dying breaths, Murphy advises the four to allow the room to fill, and use nearby scuba gear to swim 100 yards to the DSV, save for one problem: there are only three suits! One will have to drown, temporarily, to be revived in the DSV afterward.

Archer, Ray and Cyril point out that Lana ranks as the weakest swimmer among them, to which Lana reveals she’s been pregnant for several weeks! Explaining her recent mood swings, sobriety, and bigger boobs, Lana points out that Cyril isn’t the father, but rather that she had a donor impregnate her. Surprisingly, Archer immediately offers up his suit to Lana, hoping she’ll prove a better mother than his own. The water finally fills the compartment, as Archer takes his last breaths, telling Lana he loves her once underwater.

With Archer unconscious, the three race toward the DSV, and apply the defibrillator to revive him. Finally, Archer coughs up the water and returns to life, but in jokingly tickling Ray, Archer accidentally triggers the defibrillator again and shorts out the DSV.

A short while later, the group return to Cecil’s boat to wrap things up, the destruction of SeaLab paying out insurance in triplicate for its value. Ray remains confined to a wheelchair for the moment, Archer’s actions having shorted out his bionic legs, as all celebrate Lana’s impending motherhood.

As we've said time and time again, 'Archer' proves increasingly difficult to evaluate as it straddles the line between comedy and serialization. No doubt fans will recognize the conceptual similarity to last season's space-station finale, but by the same token, "Sea Tunt: Part 2" devotes precious little thought or time to the actual SeaLab conflict. Captain Murphy's plan falls apart almost as quickly as the finale kills the character off, which feels like a missed opportunity we've seen handled better before.

Lana's pregnancy notwithstanding, the episode certainly doesn't offer any closure to season-long builds like the Barry/Katya thread, which was also more or less denied to us in last year's finale. There are still plenty of gags and banter to entertain, but few that jump out of note. Lana's pregnancy and Archer's apparent confession of love will surely cause some major complications next year, but in the end we can't shake the feeling that "Sea Tunt: Part 2" wasted far too many opportunities and characters for a finale episode.

What say you? Did you get your fill of spy-spoofing ‘Archer’ action?  What was your favorite gag from “Sea Tunt: Part 2?” Join us next season for all-new ‘Archer’ recaps of season 5 on FX!

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