SPOILER WARNING: This article contains major spoilers for "Crisis on Infinite Earths, Part 3," the third installment of this year's Arrowverse crossover.

The CW's "Crisis on Infinite Earths" roped in heroes from several pockets of DC TV across multiple decades. Fans were jubilant to learn that Black Lightning (Cress Williams) would finally be brought into the Arrowverse fold in the crossover. And as it turns out, it wasn't just a glorified cameo or something trivial for the Freeland principal to be called into action.

When Jefferson Pierce joins the fray, he's thrust into the thick of things as he meets Flash at the Anti-Monitor's lair as the heroes try to find a way to stop the antimatter wave. They need Black Lightning's help and it leads to him having one of the most critical and electrifying roles in the crossover.

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When the latest Black Lightning episode concluded to tie into this event, Jefferson was taken away from his Earth by a flash of light which many assumed was Harbinger or the Monitor. It turns out it was actually Pariah who brought him to the base where the antimatter cannon was operating. However, as Black Lightning arrives, he ends up fighting with the heroes who he thinks have abducted him.

Luckily, Pariah clears the air and makes it known Jefferson's an educator, father and hero. However, Jefferson's heartbroken as his Earth was just wiped from existence, berating Pariah for not saving his family. Thankfully, Flash is able to calm him down and bring him into the fold as his powers are needed to save everyone else. A gutted Jefferson puts his emotions aside and gets to work with Vibe, Pariah, Killer Frost and the man plucked from the cosmic treadmill, Earth-90 Flash  (John Wesley Shipp) who was running to power the cannon as a prisoner of the villain.

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But with the old Flash off the treadmill, the Anti-Monitor's failsafe means an explosion will trigger and all the Earths will be killed at once rather than gradually. Finally putting their brains together, the heroes use Black Lightning to absorb all the energy from the cannon in hopes of slowing and eventually shutting it down. With the deadly effect staved off for a few minutes, the Flashes realize by one of them reversing the polarity of the treadmill, running in the opposite direction, the wave will collapse onto itself and destroy the source of the antimatter.

They have to act quickly as Jefferson's dying from absorbing so much energy. The plan begins with him stopping his absorption process, all so a Flash could get back on the treadmill. In a heartbreaking moment, though, the older Flash sucks Barry's speed away and he switches places as he thinks it's best for him to make the sacrifice. And in so doing, the cannon's destroyed as Pariah takes the heroes away in another moment of virtue from the '90s hero.

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But while Jefferson survives this clash temporally, it's a short-lived victory as he meets a dark fate moments later when he links up with the rest of this heroic league. Harbinger, possessed by the Anti-Monitor, erases the heroes, including the Monitor, on the Waverider, save for the Paragons Pariah teleported away to the Vanishing Point, which dusts the ever-defiant Jefferson away as well.

"Crisis on Infinite Earths" will return after the winter hiatus. The crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.

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