The best moment of the episode barely even requires dialogue. When Archer first encounters Conway and goes on an inexplicable "revenge rampage", Lana barely bats an eye. Instead, she takes her sweet time making tea while Archer and Conway savagely destroy the apartment, stepping in at just the right time to break it up with a well-placed blow. The entire scene is absolutely insane yet so perfectly normal for everyone involved that you just accepts what's happening even while laughing.
Of course, Archer's also very good at balancing insane comedy with surprising character moments, which brings us to the emotional center of the episode. When the mission begins, Archer quickly realizes that if he and Lana are both killed, someone else will have to step in and raise Abbiejean. But when he suggests his mother adopt the baby, Lana quickly dismisses the notion for what seems like obvious reasons (to everyone but Archer anyway). But as Archer presses the issue, sometimes in between gunfights, Lana eventually reveals the truth: If she were to die, Abbiejean would live with her parents instead of with Archer and his family.
Archer is understandably stunned by the response, even though his between-season escapades should have proved he's a less-than-ideal single dad. It's a pretty safe bet this matter will come up again in the future, even if Archer and Lana didn't already have a fairly tumultuous relationship.
Of course, Lana apparently isn't against Malory babysitting Abbiejean while she and Archer are away on assignment. The episode's subplot deals with Abbiejean being left with the office staff, and if you think that's frightening you'd be right. While Malory is refreshing her drink, the baby disappears, sparking her ferocious maternal instincts as she tries to figure out what happened. It takes a little too long to find Abbiejean than anyone should be comfortable with, but it prompts some great moments as Malory, Cheryl, and Pam try to find it while simultaneously harassing each other.
Of course, thinking about the matter for two seconds should reveal who Abbiejean is with: Krieger, who is studying her on his lab table while disturbing baby skeleton chalk drawings fill up the nearby board. The whole affair seems to be a misunderstanding, so don't expect Cyborg Abbiejean to appear anytime soon. Not that it stops Malory from covering up the incident while making very overt threats to Krieger's manhood if he steps out of line again.
Meanwhile, in Argentina, history mostly repeats itself. Conway reveals that he's a traitor after all and shoots Archer in the back to mix things up. But sparing Lana because she's a mother wasn't a great idea, and Conway horrifically loses another hand for his trouble. On principle, I want to say Archer is unnecessarily repeating itself, but this show has always had some level of self-awareness. Besides, the scene is far better executed thanks to a half-decade of experience among Archer's cast and crew. Even if the joke wasn't five years old, it's referential humor done right.
Although now we have to see if the rest of Season 6 will go the same way.
Bottom Line: "Three to Tango" perfectly replicates the spy formula of Season 1 (right down to repeating plot points from an earlier episode) but the comedy formula is so refined that everything feels fresh and exciting. Well paced, solid jokes, and an emotional reveal that will definitely impact future episodes makes this mandatory viewing for any Archer fan.
Recommendation: Did you miss my "mandatory viewing" remark? This is Archer at its best.