A bevy of Star Trek stars are coming together in the fight against epilepsy this weekend, and you have the chance to join them.

The Epilepsy Foundation is hosting an event called END EPILEPSY Live! On Saturday afternoon. It’s a fundraising telethon broadcast live from Hollywood on YouTube, CBSLocal.com, and the Epilepsy Foundation’s website. The event will be hosted by actor Greg Grunberg, who is the Foundation’s spokesperson, and whose son suffers from epilepsy. Along with Grunberg, a whole host of celebrities are scheduled to appear, including many with ties to Trek. Among them: William Shatner, Brent Spiner, LeVar Burton, Marina Sirtis, Chris Pine, and J.J. Abrams.

In addition to watching the show and making a contribution, you also have the chance to be a part of it. Since host Grunberg has the distinction of being one of the only actors to have appeared in both the Star Trek and Star Wars franchises, he’s asked fans to send in selfie videos explaining: are you Star Wars or Star Trek? When you post a selfie video on Twitter or Instagram using #TeamTrek or #TeamWars and the hashtag #EndEpilepsyLIVE, you could earn yourself a shout-out from Grunberg, or have your video played during the event on Saturday.

Once again, END EPILEPSY Live! Is happening this Saturday, November 9th, from 2pm to 6pm Pacific time. You can watch it on YouTube, CBSLocal.com, or the Epilepsy Foundation’s website. Donations will go to supporting the more than 3.4 million people in the United States living with epilepsy.