In 2012, the TV channel CW piloted a new show called “Arrow” based on the DC comic book character Green Arrow.  In 2014 “The Flash” premiered on the CW and “Arrow’s” main character Oliver Queen appeared in the pilot, seemingly connecting the two shows.

Later in 2014, the two shows further strengthened their ties with a two-episode story titled “Flash vs Arrow.”  The event began in a “The Flash” episode and finished in an “Arrow” episode.

The new tradition of an annual crossover continued in 2015 with another two-part story called “Heroes Join Forces.” This crossover added more action, more heroes, and more villains. Some of the new heroes along with some of the old ones went on to be a part of a new show called “DC’s Legends of Tomorrow.” This show was also a part of this shared universe that fans began to call “The Arrowverse.”

Meanwhile, a show on CBS called “Supergirl” piloted, leaving fans to wonder if it was part of “The Arrowverse.” In 2016, “Supergirl” joined the other three shows in a three-part crossover called “Invasion!” Then, 2016’s crossover was even bigger than previous crossovers. It featured the 100^th episode of “Arrow.”

The crossover in 2017 called “Crisis on Earth X” was a four-episode event that featured the most heroes working together in the history of “The Arrowverse.”

This was followed by 2018’s “Elseworlds” crossover that mainly served as a setup for 2019’s “Crisis on Infinite Earths.” “Crisis on Infinite Earths” is a five-episode crossover event featuring “Arrow,” “The Flash,” “DC’s Legends of Tomorrow,” “Supergirl,” and a new show to “The Arrowverse” called “Batwoman.”

This five-part event adapts a story from the comic book event of the same name. Although it is an adaptation, it is not a direct adaptation and there are many differences between the show and the comic. The comic book event is more of an inspiration for its TV counterpart. “Crisis on Infinite Earths” features many characters from all five shows that are beloved by fans, but it does not stop there.

The heroes from these five shows are not the only people included in the crossover, because there are many other cameos from other shows and movies. A character from Tim Burton’s 1989 film, “Batman” appears in the crossover. Burt Ward makes an appearance as Robin from the 1966 series “Batman.” Robin and The Hawk also make an appearance from the show “Titans.” Those are just a few examples of other shows and movies that crossed over with the rest of “The Arrowverse” during “Crisis on Infinite Earths.”

The scale of this crossover is unmatched in television history. If you want to watch “Crisis on Infinite Earths” the first three episodes can be streamed for free on the CW app. Episodes four and five will air on Tuesday January 14^th at eight and nine p.m.