Even with 22 episodes or more at their disposal, emotional catharsis isn't necessarily a strong suit of shows like Arrow. Programs of its ilk tend to move from one plot point to the next in rapid fashion as a way to keep the story flowing in what has become an increasingly rare form of television programming – even by broadcast TV standards. As such, when a couple like, say, Oliver and Felicity breaks up, the show will often times go out of its way to underline what the two characters once had between them, but it's not too often that a show will find time in its busy schedule – especially with a big bad like Prometheus on the loose – for two formerly romantic partners to have an occasion to hash things out.

Ever the innovator in what has been a turnaround fifth season Arrow finds time with just a handful of episodes left to do just that. Last week's 'Dangerous Liaisons' ended with Felicity using the heartbeat-tracking device to locate Prometheus. Much to her and Oliver's surprise/dismay, the two discovered the villain's heartbeat was coming from inside Team Arrow's bunker, which he promptly blew up because part of always being ten steps ahead is planting explosive devices on the computer terminals and rigging them to explode at the most dramatically opportune moment.

As such, 'Underneath' finds itself poised to deliver a late-season episode that will continue the overarching story of Oliver questioning his legacy by forcing him to face his most recent failed relationship and perhaps come to terms with the woman he nearly married. The choice is an odd one this late in the season, yet it makes for a surprisingly satisfying hour of television that clears away a considerable amount of clutter to allow two characters who have been around since the very beginning (well, almost) a chance to reconcile with the people that they have become over the past five years and some of the decisions they have made in that time.

Arrow Season 5 Episode 20

Granted, much of that focus remains on recent decisions, like Oliver's revelation that he's essentially a serial killer and his subsequent choice to put the Green Arrow costume aside for the time being, and Felicity's choice to join Helix in a circuitous attempt to exact revenge on Prometheus for his role in the death of her boyfriend. As with any good therapy session between former lovers, the discussion eventually turns to what went wrong between them, as Felicity and Oliver eventually retrace their steps back to William and the fact that the son of Green Arrow was kept a secret from the woman who was going to be vigilante's wife.

In DC TV show time, the dissolution of Olicity is basically ancient history, but to its credit, 'Underneath' is effective in making the prospect of their coupledom and the notion of Oliver's son seem narratively relevant again, even though the focus on the latter becomes the crux of the episode and the season's narrative moving forward. But the hour handles the execution of its circumstances well, essentially turning the Arrow Bunker into a death trap because Cisco designed it almost too well, thereby giving what is more or less an hour of two characters talking about their past a sense of urgency as Oliver and Felicity's attempts to escape are matched with the rest of Team Arrow figuring out a way to set them free.

Stephen Amell and Emily Bett Rickards in Arrow Season 5

While there is plenty of drama between Oliver and Felicity in the present, the constraint of their current situation keeps them from doing a total deep dive into their past – a fact that requires the use of Arrow's favorite narrative device: the flashback. This time, though, the show journeys back just a short while to simpler time when the Green Arrow's sleeves were shorter and Curtis was more interested in play matchmaker than building T spheres. The flashback sequences underline the notion that a spark between Oliver and Felicity is still a possibility and that despite the diverging paths they recently found themselves on, the two continue to have genuine feelings for one another.

Unlike the other big swing Arrow took in an episode this season, 'Underneath' works because it allows the writers to plumb the depths of a relationship they have clearly been interested in exploring, even though it proved to be so divisive amongst the viewership. It's hard to gauge, then, just how invested the much of the audience will have been in this exploration of romantic entanglements and Oliver's continually muddied search for identity, but for a late season effort, a mandatory couple's therapy session between two main characters makes for an interesting departure from the ongoing Prometheus storyline.

Next: John Barrowman Not Returning to Arrowverse Next Season

Arrow continues next Wednesday with 'Honor Thy Fathers' @8pm on The CW.