Danny Trejo's signature deadpan delivery and menacing presence make themselves at home at STAR Labs in an exclusive clip from tonight's episode of The Flash.

In the clip, which was provided to ComicBook.com by The CW, Team Flash (Joe West, Barry Allen, and Harrison Wells) meets Gypsy's dad Breacher for the first time. It is...not an ideal meeting.

"We just thought it would be a great episode," executive producer Andrew Kreisberg recently said. "Gypsy and Jessica, they’re so tough and so strong. We’re like, 'Obviously she came from somebody strong,' and we just thought it would be a hilarious idea for Cisco, who’s managed to melt Gypsy’s heart, being unable to do the same with her father."

Kreisberg also revealed the process that went into casting Trejo, which was something the show's writers had initially thought was out of the realm of possibility.

"We were in the room and we were like, 'Who could we get?' and someone said Danny Trejo and we all started laughing like, 'He’d be great, but of course Danny Trejo’s not going to do this,'" Kreisberg added. "But as I’ve discovered over these past few years, if you don’t ask, you don’t get it. So we reached out to him and his people, and it turned out he was a fan, and he was eager to do it, and he loved the character."

"I flipped out. [laughs] I geeked out, for sure. I completely geeked out!" Said Jessica Camacho, who plays Gypsy, of her on-screen dad's casting. "I have been such a big fan of his for years, and, man. He's just the coolest. He's iconic in his badass-dom; I just thought that that was a perfect fit....They couldn't have nailed it any better. And once he showed up, seeing what he brings -- it was such a pleasure to work with him, because he brings so much. He strikes fear into anybody who looks at him, but also, because I get to play his daughter, I got to see him be lovey, and he's just really funny. He's so many things, so it was such a joy to work with him and to see him fill out and flesh out his character."

(Photo: Warner Bros. TV/The CW)

In the episode, directed by series regular Tom Cavangah, Cisco (Carlos Valdes) is shocked when Gypsy’s (guest star Jessica Camacho) father, Breacher (guest star Danny Trejo), shows up on Earth-1. Breacher takes an immediate disliking to Cisco and decides to hunt him. Meanwhile, Barry (Grant Gustin) runs into his old nemesis, Ralph Dibny (guest star Hartley Sawyer). The episode was written by Sterling Gates, who co-wrote Justice League of America's Vibe with DC chief creative officer Geoff Johns.

The Flash airs on Tuesday nights at 8 p.m. ET/PT on The CW.