SPOILER ALERT: Do not read if you have not yet watched the Jan. 14 conclusion of “Crisis on Infinite Earths.”

More than a month after it began, the “Crisis on Infinite Earths” crossover event crashed to a close Tuesday night on the CW with back-to-back episodes of “Arrow” and “Legends of Tomorrow” that brought the action back to one, unified earth — oh yeah, and also tied the DC film and television universes together.

The emotional first hour picked up at the Dawn of Time, bringing viewers into a Monitor/Anti-Monitor (LaMonica Garrett) origin story where the former’s ambition “doomed them all.” Meanwhile in the present day, the seven Paragons continued to be stuck in the Vanishing Point, a situation made even worse by Barry/Flash (Grant Gustin) disappearing for months (or, a moment in his timeline).

That left the newly dead (but assembled essence) Oliver/Green Arrow (Stephen Amell) to return as a memory-seeking guide of sorts, who revealed the key to saving everyone was indeed the Speed Force that Barry was seeking. He also revealed it was up to Barry to find the heroes by relying on his own memories, essentially saving everyone in the process. So, no pressure.

As Barry raced to find his cohorts, he ran into another alternate Flash (Ezra Miller), essentially tying the Justice League and Arrowverse together, as well as Oliver, who finally revealed the sacrifice he’d made to save Barry and Kara/Supergirl (Melissa Benoist).

Meanwhile, Lex (Jon Cryer) revealed he’d given himself some powerful upgrades by knocking out Kara and Ryan Choi (Osric Chau) and dashing off in search of universal domination. That meant tracking down Monitor and trying to mount his own side-plan, but thanks to Kara’s quick action, she stopped him in his tracks while Ryan convinced that iteration of Monitor not to go through with his plans. It worked, but it ultimately wasn’t enough, and all the Paragons wound up at the Dawn of Time where Anti-Monitor revealed they had all met their destiny (aka holding the line and fighting the Dementor-like “flying things” long enough to rebuild the universe).

That left Oliver to face off against Anti-Monitor and “light the spark,” while the Paragons united to “fan the flame.” In the end it was Oliver who lost his life (again) to mark “an end,” prompting the new universe to ultimately be born.

In the second hour, that universe was fully intact — but it came with a few small changes, such as Lex Luthor now being an award-winning humanitarian. One by one the Paragons realized they were now all on the same Earth, with a little nudging from a cameo-making Marv Wolfman.

As the other heroes caught up with the Paragons and learned their new fates via J’onn J’onzz’s (David Harewood) brain-zapping powers, they realized they were still a man down, as Oliver was nowhere to be found. There were bigger issues at play, though, when Beebo finally made an appearance as a giant version of himself, which Sara (Caity Lotz) and friends took down after they realized he was meant to be a distraction during a bank robbery.

With the giant, sacred toy out of the way a path was cleared for Nash (Tom Cavanagh) to return and warn the heroes that there was still a surprisingly large amount of anti-matter among them because, as it turned out, even though Oliver gave his life for the new universe, it wasn’t enough to defeat Anti-Monitor.

Enter Ray (Brandon Routh) and Ryan, who devised a plan to infinitely decrease Anti-Monitor’s size and send him into a “microverse,” where humanity would be safe for the rest of eternity. But before they could build the device that would do that, the other heroes banded together for one final showdown, in which Anti-Monitor grew to Marshmallow Man type proportions.

Luckily, the gang was able to hold the big bad off long enough for the device to be built, and Ray ushered it in just in the nick of time, activating it and throwing it to Kara. With one giant hurl she threw the ball-like anti-matter bomb straight into Anti-Monitor and sent him away for good, clearing the way for a happy ending for all the superheroes.

The crossover wrapped with an address from the U.S. president, who acknowledged Oliver’s death in front of the nation and called for a moment of silence on behalf of the fallen hero. Then the team of remaining heroes — including Jefferson Pierce/Black Lightning (Cress Williams) each gave their own farewell to Ollie in front of a displayed costume, housed in a new clubhouse of sorts designed for the team the next time they need to assemble to save the world.

Or, to put in another crossover.