Supergirl star Mehcad Brooks revealed that he received death threats after James Olsen and Lena Luthor kissed in Season 3.

Brooks mentioned the threats as a way to highlight Black Lives Matter's ongoing fight against racism and discrimination. "Don't believe this is real yet?" Brooks wrote on Twitter. "I almost skipped ComicCon 2019 because of death threats I received on Twitter for kissing Katie McGrath I had to demand extra security and metal detectors. I lost sleep over that. We are tired of being stuck in between hopeless and hopeful."

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Upon making the revelation on Twitter, a Supergirl fan decided to create a petition to get Katie McGrath (Lena Luthor) kicked off the show. The petition has gained little traction amongst the fandom.

After hearing about the fan-started petition, Brooks took to Twitter to stop fans from harassing McGrath. He wrote, "Hey guy my mention of the death threats I received prior to Comicon over kissing Katie McGrath are not her fault. STOP ALL PETITIONS ON MY BEHALF. YOUR PASSION IS HEARD BUT HEAR ME TOO. I WAS MAKING A POINT ABOUT HOW MUCH OF A REAL THREAT WHITE SUPREMACY IS. KATIE IS KINDNESS."

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He followed the tweet up by writing, "Please take my original tweet about the death threats as what they were. A look into how widespread white supremacy is. Katie McGrath has always been supportive and is one of my dearest friends and anti-racist allies. She is NOT the problem. She stands with Black Lives Matter."

Brooks portrayed Olsen on The CW series from Season 1 until his departure during Season 5. He will be seen next in the Mortal Kombat reboot as Jax Briggs.

Returning to The CW in mid-2021, Supergirl stars Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter, Chyler Leigh as Alex Danvers, Nicole Maines as Dreamer and Jesse Rath as Brainiac-5.