The 56-year-old actress and 67-year-old director cosplayed as Vega and Dr. Bosconovitch at the annual fighting game tournament. The first Evolution Championship Series took place in 2002.
The couple attended the event as part of a high school graduation trip for their 19-year-old son Thomas, who dressed as Dee Jay. Curtis' older sister, actress Kelly Curtis, went as Makoto.
"Grad trip to @evo2k. 2 stay incognito was Vega who wears a mask. @StreetFighter family. DJ, Dr. Bosconovich, Makoto," Curtis tweeted. "@evo2k and the gaming community so warm and welcoming. What lovely people."
Curtis will next portray Dean Cathy Munsch on new Ryan Murphy series Scream Queens, which will premiere Sept. 22 on Fox. The horror-comedy program takes place on a college campus, and co-stars Emma Roberts, Lea Michele and Abigail Breslin.