‘The Flash,’ ‘Supergirl’ Musical Crossover Spoilers: ‘Legends Of Tomorrow’ Star Victor Garber Added? ‘Gotham’ Crossover With The CW Multiverse Possible?

Since "Supergirl" joined "Arrow," "The Flash," and "Legends of Tomorrow" on The CW the DC television universe gained the opportunity to showcase a crossover between the four superhero shows. True enough, a massive three-part crossover featuring the four shows was announced. Now, it looks like that "The Flash" and "Supergirl" would have another crossover -- and this time is going to be a musical.

The musical crossover of "The Flash" and "Supergirl" is fitting, given that the shows' lead stars (Melissa Benoist and Grant Gustin) both had parts in Fox's "Glee," Screen Rant reported. It should be noted as well that Jeremy Jordan (Winn Schott) of "Supergirl" and "The Flash" actors Jesse L. Martin (Joe West) and Carlos Valdes (Cisco Ramon) are all Broadway veterans.

Despite these possibilities, details about "The Flash" and "Supergirl" musical crossover episode yet. There are speculations, however, that an accomplished vocalist from "Legends of Tomorrow" would appear in "The Flash" and "Supergirl" musical crossover, which will air near the season's end.

Broadway veteran Victor Garber (Martin Stein on "Legends of Tomorrow") is speculated to join "The Flash" and "Supergirl" musical crossover, according to Comic Book. Executive producer Greg Berlanti addressed Garber's possible participation in the musical, saying that he'd "be crazy not to" involve the actor because "he's got one of the best voices" in the entire multiverse.

If Garber doesn't appear in the musical crossover of "The Flash" and "Supergirl," fans still saw the actor display his vocal talents. In a recent "Legends of Tomorrow" episode, Garber pretended to be a famous Nazi singer and sang for the crowd.

Another DC TV series has joined the crossover possibilities. That is "Gotham," which currently airs on Fox.

A "Gotham" crossover with "The Flash," "Supergirl," "Arrow," and "Legends of Tomorrow" could work but there are some hindrances in there as well. For instance, "Supergirl" does not exist within the same Earth as "The Flash," "Arrow," and "Legends of Tomorrow" but there's a way to travel between the timelines. Now, "Gotham" began with characters that don't have real powers but Hugo Strange's (BD Wong) experiments could change that, CarterMatt wrote.

There's the matter of the TV network the shows are in, too. "Gotham" and "Arrow" may both hail from Warner Bros., but Fox agreeing to a crossover is highly unlikely just like CBS and "Supergirl." A crossover between the shows, however, can be possible if "Gotham" moves to The CW. The dark and gloomy visuals of "Gotham" don't fit with the bright colors of "Supergirl" and "The Flash" as well.

Thoughts on "The Flash" and "Supergirl" musical crossover? Should "Gotham" cross paths with the CW multiverse? Comment below!