For one night only—tonight, January 3—actress and AIDS activist Gloria Reuben will reprise her role as HIV-positive former medical assistant Jeanie Boulet on NBC’s longtime medical drama ER, TV Guide Online reports. She played the character from 1995 through 1999, when Jeanie remained one of the few HIV-positive series regulars on network television (, 1/3).

On the episode, Jeanie returns to County Hospital when her adopted son—who is also HIV positive—passes out in gym class. After he is rushed to the emergency room, doctors find a spot on his brain and run tests to determine whether he has a lymphoma, an early sign of full-blown AIDS.

“Even though I’m doing just one episode on ER, it’s a very powerful one,” Reuben told TV Guide. “And if [HIV/AIDS] is brought back into people’s awareness even for a minute, it’s a good thing.”

Reuben recently appeared alongside POZ editor-in-chief Regan Hofmann as the narrator for Cable Positive’s Women and HIV, the third installment in the award-winning Positive Voices documentary series.