A recently leaked Sony email may have finally revealed why Marvel has stalled so long with producing a female superhero movie.

The email leaked is between Marvel CEO Ike Perlmutter and Sony CEO Michael Lynton with the subject line, "Female Movies," courtesy of Wikileaks. It follows:

Michael,

As we discussed on the phone, below are just a few examples. There are more.

Thanks,

Ike

1. Electra (Marvel) - Very bad idea and the end result was very, very bad. http://www.boxofficemojo.com/movies/?id=elektra.htm

2. Catwoman (WB/DC) - Catwoman was one of the most important female character within the Batmanfranchise. This film was a disaster. http://www.boxofficemojo.com/movies/?id=catwoman.htm

3. Supergirl - (DC) Supergirl was one of the most important female super hero in Superman franchise. This Movie came out in 1984 and did $14 million total domestic with opening weekend of $5.5 million. Again, another disaster.

Best, ?Ike

It is no secret that a lot of comic female heroines are a hard sell, but it also fair to note that a lot of male superhero films did quite poorly in those generations also.

This email links back to the Black Widow argument in that her appearance in the MCU hasn't yet granted her her own solo film.

"Marvel has come under scrutiny in recent months after not announcing a Black Widow movie even though Scarlett Johansson has played the character in four movies that were tremendous box office hits. Yet the studio hasn't solidified its support for her to star as the leading role. Last year they did, however, announce nine movies to be released before 2020, one of which, 'Captain Marvel', will be led by a woman," writes Huffington Post.

DC and Warner Bros. also plan to release 'Wonder Woman' a year prior to Marvel's 'Captain Marvel.' The superhero genre pool will only expand until then, making it more interesting to see how these female lead films fair in the market.