The two have been dating for two years, and Esmail, 37, directed Rossum, 28, in the 2014 rom-com Comet. The actress was previously married to music executive Justin Siegel, but they divorced in 2010.
Rossum continues to entertain as Fiona on Showtime's comedy Shameless, which will enter its sixth season in January. Meanwhile, Esmail is quickly earning acclaim as the creator of the new summer series Mr. Robot, which airs its first season finale on Wednesday at 10/9c on USA.
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