As a member of the camera crew on The Flash, Jeff Cassidy knows some people in high places. The filmmaker was able to enlist Emily Bett Rickards from Arrow, Tom Cavanagh from The Flash, and Josh Dallas from Once Upon a Time to star in “Sidekick,” his 15-minute short film about a father who weaves a superhero tale for his son.

Rickards and Dallas take on dual roles as parents dealing with tragic news and characters in the story. Dallas plays superhero Captain Strong, Rickards plays a princess in need of rescuing, and Cavanagh plays another villainous role as Darkman. The son is played by Christian Michael Cooper, soon to be seen in the Prison Break sequel series.

“The director, Jeff Cassidy, came to me,” Dallas says in a behind-the-scenes video (shown below). “He wrote this script. It was a beautiful script about a man who was dealing with his own mortality and how he then conveys that to his young son and the struggles that he goes through with his wife in order to deal with his impending death. That’s what drew me to the part.”

Cassidy and his crew also shared set photos on Instagram, including the showdown between Captain Strong and Darkman. The scene was shot in Vancouver, where The CW typically films Arrow, The Flash, and now Supergirl.