The actress told The AP that it's fun playing siblings Bridget and Siobhan on the CW thriller, but admitted that it can sometimes get confusing to keep their backstories straight.
"It's a group effort [to play the twins] - hair, make-up, wardrobe. Besides, as identical twins, Bridget and Siobhan have characteristics that are inherently very similar," Gellar explained. "So you don't have to worry - they have to be able to be confused for each other."
She added: "[It's just tough] keeping in mind who knows what and who doesn't know what."
Gellar also revealed that she has really enjoyed taking an active creative role on Ringer as a producer.
She explained. "I don't have to waste time worrying about what they're doing with my character and my story line. I get to make the show I want to make.
"Since I'm on-set most of the time, if there's a decision that has to be made while we're shooting, I can make it, as opposed to calling upstairs. So I can help keep things moving along."
Gellar previously revealed that her previous seriesBuffy the Vampire Slayer consumed her life for many years.
Ringer airs Tuesdays at 9/8c on The CW.
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