Zack Snyder may not have thought Grant Gustin was the right fit for the big-screen "Justice League," but William H. Macy certainly liked what he saw in the "Flash" star.

Deadline reports Gustin has boarded Macy's "Krystal," joining Rosario Dawson, Nick Robinson, Felicity Huffman, Kathy Bates, John Leguizamo, Joe Manganiello and Macy himself in the indie comedy-drama

Macy's third directorial effort, "Krystal" centers on a young man with a heart condition who enters into an unlikely love affair with an older woman who's an ex-prostitute and junkie on the run. It's set to begin filming next month in Georgia.

The 26-year-old Gustin, whose breakout role came with "The Flash," previously appeared in the 2014 indie film "Affluenza."