Sarah Michelle Geller in 'Ringer': What the Critics Are Saying

What It's About: Ringer, originally developed for CBS, revolves around a woman (Gellar), who after witnessing a murder, goes on the run, hiding out by assuming the life of her affluent identical twin sister. She learns her sister's "perfect" life isn't so perfect after all.

The actress looks "confused and meek" while tackling dual roles of twin sisters in the CW’s new series, writes THR's Tim Goodman, though USA Today's Robert Blanco praises Gellar for her "two very good, well-defined" performances.

Sarah Michelle Gellar marks her return to series TV on Tuesday night.

The Buffy the Vampire Slayer star takes on two roles in CW's new drama Ringer, which airs at 9 p.m.

In the show, Gellar plays twin sisters Bridget and Siobhan. Bridget, a stripper and drug abuser who is being hunted by an FBI agent mobster, takes on the identity of her sister Siobhan after the latter winds up missing -- presumably having killed herself. But she soon learns that Siobhan is herself being tracked down by an assassin.

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So what do the critics have to say about Gellar's performance in two roles?

The Hollywood Reporter's Tim Goodman writes that the series doesn't play to her strengths.

"The downside to Ringer is that unless you're weaned on The CW's fare, it really doesn't have a lot of weight, and Gellar seems stretched a bit thin playing dual roles," he writes. "In Buffy, she was a major ass-kicker with a smart-aleck streak. In Ringer, she's called on to be mysterious, both downbeat as Bridget and high-class as Siobhan, but ends up looking confused and meek. It hardly lends confidence that she's capable of being the cornerstone of such a show."

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Mary McNamara of the Los Angeles Times echoes that sentiment, writing that "Gellar has a hard time playing one troubled and complicated woman, much less two." She adds that that's partly to blame on creators Eric C. Charmelo and Nicole Snyder and director Richard Shepard, who "spend so much time and energy establishing how different the women are that there's not much left over to make them believable."

"Still, there remains something undeniably compelling about watching a person try to fake their way through another person's life, McNamara adds. "Although no one would call Gellar a subtle performer, her Bridget-as-Siobhan is engaging and likable."

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On the other hand, USA Today's Robert Blanco praised the actress, writing that she gives "two very good, well-defined" performances.

"There's a warmth that seeps through when she's playing Bridget pretending to be Siobhan that isn't there when she's Siobhan alone, which is both a wise acting choice and a way for us, at least initially, to tell them apart," he writes.

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Mike Hale of the New York Times also offers praise to Gellar.

"She brings the same matter-of-fact soulfulness to the mystery story of Ringer that she did to the Gothic romance of Buffy," he writes, adding that "elaborating on the twin-sisters-in-peril premise without descending into camp may prove to be too much of a challenge for the producers, but Ms. Gellar deserves our indulgence, at least for a few weeks."

David Wiegand of the San Francisco Chronicle was more effusive his praise of the actress.

"The show is great fun, and clearly the star herself is having fun in the lead roles," he writes. "While carefully showing us the differences between the twins, Gellar also has to make us understand how much they are alike, well beyond such things as income levels and hairstyles. As the show continues, those similarities and differences should maintain our attention even beyond all the plot complications."