Heroes of the Zeroes is Nick Rogers’ daily, alphabetical look back at the 365 best films of 2000 to 2009.

2004’s Before Sunset infused its free-form, 80-minute marathon of conversation with intimate character insights that surpassed will-they-or-won’t-they banter.

That’s because gone are Jesse (Ethan Hawke) and Celine (Julie Delpy) as the young impromptu lovers of 1995’s Before Sunrise, who shared a romantic Vienna night and in whose ambiguous separation there was still promise.

Nine years of what-ifs have injected awkwardness into once freewheeling conversation. Tentative pecks. Deflective laughter. Stomped-on conversations. This happens when she meets him in Paris during his book tour for a novel based on their night.

Hawke, Delpy and director Richard Linklater collaborated on the Oscar-nominated screenplay for one of the decade’s least likely, but most satisfying, sequels.

Before Sunset carries the urgency of powerlessly watching friends sink into emotional distress, as well as ticking-clock finality — from time, happenstance and weariness with what the world has since thrown at the duo. Plus, even those in healthy relationships can identify with wondering what would’ve been, as both Jesse and Celine painfully, candidly recollect their paths.

Wishing and wondering can fulfill them no more, and whether they rekindle their spark generates as much suspense as any thriller.

As a romance shot through with regrets, obligations and fears, Sunset built up to a wistful, perfect conclusion — the passionate husk of Nina Simone’s voice, a fadeout built on the idea that a memory’s never finished as long as you’re alive and — well worth swooning over — one of the loveliest last-line exchanges of all time.