The epic five-part Arrowverse crossover “Crisis on Infinite Earths” ended with characters who had originally hailed from three different universes uniting as a Justice League on a single Earth-Prime. This unification could have, in theory, heralded an era of even greater connectivity among the various series that make up The CW’s entries into the DC Extended Universe. Instead, the arrival of the global COVID-19 pandemic and its attendant safety protocols squandered that promise and necessarily put fans’ dreams of a genuine small-screen Justice League adventure on an indefinite hold.

Pre-Crisis, a crossover involving, say, Green Arrow, Flash and Supergirl required a threat big enough to warrant universe hopping. Jumping between Earth-1 and Earth-38 to stop Captain Boomerang wouldn’t have seemed worth the effort. However, once the composite Earth-Prime came into existence, it should have become easy for heroes like Superman and Batwoman to consult each other on cases. In fact, this greater ease of character interaction seemed like one of the primary benefits of adapting “Crisis on Infinite Earths.” If everyone is on the same Earth, they can visit each other more freely.

RELATED: The CW Renews Seven Shows Including Flash, Superman & Lois and Riverdale

Crisis On Infinite Earths Didn't Save the Arrowverse, It Doomed It

Unfortunately, a global pandemic means that each individual show must stay as insular as possible. Crossovers mean more cast and more crew and a much greater chance for people to get sick. As a result, the shows of the Arrowverse have, more or less, felt independent from one another for the last two years.

There have been some exceptions to this series isolation. Last year, David Ramsey’s John Diggle popped up in each corner of the Arrowverse, providing early-MCU Phil Coulson-like connective tissue, and the current season of The Flash started with the five-part “Armageddon,” which featured characters from Arrow, DC’s Legends of Tomorrow, Black Lightning, Supergirl and Batwoman. However, most of the character crossovers in “Armageddon” took place in a future that Barry Allen has since averted.

RELATED: Superman & Lois May Be Setting Up Season 3’s Big Threat, And It Isn’t [SPOILER]

CW Arrowverse Posters in a split image.

The realities of COVID safety protocols mean that another giant crossover event like “Crisis on Infinite Earths” is unlikely to happen in the immediate future, but that doesn’t mean that the creators of the remaining Arrowverse shows can’t take steps to make Earth-Prime feel more connected. The Flash could swing by Smallville to help Clark and Lois better understand the mechanics of crossing over to the Bizarro universe. J’onn J’onzz could come to Central City to help read the mind of the sentient black fire currently terrorizing Team Flash. And anyone on Superman & Lois could say something about Supergirl going public with her secret identity.

With Supergirl and Black Lightning already finished and Batwoman and DC’s Legends of Tomorrow facing possible cancelation, it may already be too late to ever deliver on the promise of an Arrowverse Justice League. Then again, the “Armageddon” arc on The Flash shows that a series ending doesn’t mean that all of its characters have to ride off into the sunset. There’s no reason, aside from actor availability, why heroes from defunct shows can’t pop up here and there or even take part in major crossover events once they become feasible again.

COVID-19 may have changed the landscape of the Arrowverse and forced show creators to pare down or delay some of their more ambitious story ideas, but the pandemic won’t last forever. In the meantime, finding ways to show that the heroes of these different series know and work with each other could go a long way to show fans that the post-Crisis Arrowverse can still follow through on the promises it made two years ago.