[2][3] The series stars Sarah Michelle Gellar, who plays twin sisters Bridget Kelly and Siobhan Martin.

She is under the protection of FBI Agent Victor Machado (Nestor Carbonell), having agreed to testify against her employer, local crime boss Bodaway Macawi (Zahn McClarnon), whom she witnessed committing murder.

Fearing that Macawi, who has already murdered several witnesses linking him to previous crimes, will also kill her, Bridget flees to New York to meet her estranged twin sister Siobhan (also played by Gellar).

Soon after Bridget's arrival in New York, Siobhan, who had kept her sister's existence secret from her family, appears to commit suicide by jumping into the ocean.

Next to be cast was Nestor Carbonell as Victor Machado,[20] followed by Ioan Gruffudd as Siobhan's husband Andrew Martin, and Mike Colter as Bridget's sponsor Malcolm Ward.

[22] It was reported on July 19, 2011, that Jaime Murray had been cast as Olivia, Andrew's business partner, who first appeared in episode two and became a recurring character.

[28] On September 3, Nicole Gale Anderson revealed on her official Twitter that she joined Ringer and will play the role of Monica.

[34] Later in the season, along with "Glory Box" by Portishead,[35] "Video Games" was featured for the first time on prime spot on Ringer on September 28, 2011 during a pivotal scene.

[36] Adele's song "Set Fire To The Rain" was used for the promotional campaign of the show[37] and "Rumour Has It" during the last scene of the mid-season finale.

The series made its debut at Comic-Con 2011 with cast members Sarah Michelle Gellar, Nestor Carbonell, Ioan Gruffudd and Kristoffer Polaha.

In addition, Gellar was featured in a photo shoot for The Hollywood Reporter entitled Comic-Con: TV's 6 Most Wanted Women.

[68] Sarah Michelle Gellar, Nestor Carbonell, Ioan Gruffudd, Kristoffer Polaha and Mike Colter attended "The Television Critics Association Summer Tour" to promote Ringer.

One of TV's most iconic stars is back with a twisty new drama, Ringer: 'It's what audiences want to see me do – It's Cruel Intentions meets Buffy'".

[75] On September 11, 2011, Sarah Michelle Gellar made the cover of The New York VUE, the TV magazine included every Sunday in The Daily News with the tagline "Doubling Back.

[76] On September 12, 2011, Sarah Michelle Gellar was on Late Night with Jimmy Fallon and on Regis and Kelly the following day to promote the pilot.

[80] On February 6, 2012, Gellar was a guest on Andy Cohen's "Watch What Happens Live" with Ryan Murphy[81] and on the Late Show with David Letterman.

[89] Matt Mitovich of TVLine gave the pilot a positive review stating, "the set-up is sound, with some loose ends addressed and nice details sprinkled in.

Tackling multiple roles, Gellar does a fine job as in-too-deep Bridget, icy Siobhan, and Bridget-as-Siobhan, and the supporting cast presents no weak link.

"[91] The New York Post gave a positive review giving 3/4 stars saying the pilot is "so good that it's CBS' bad" for having given away Ringer to the CW.

[95] Newsday likewise commented that while Sarah Michelle Gellar looks "stunning", the show doesn't fit the network as "it's inert, lackluster and a trifle old-fashioned", and gave it a C+ grade.

[96] Matthew Gilbert of ''The Boston Globe was more negative about Ringer, handing it a "D" grade as well as calling the special effects "lousy" and "sloppy", and "the story line – ripped from a cheesy daytime soap".

[98] The Friday after its debut, The CW broadcast an encore of the pilot episode which drew 1.87 million viewers and a 0.6 Adults 18-49 rating.

The CW put the Canadian series The L.A. Complex in its time slot after the finale, in hopes that show would produce higher ratings.

[127] On August 25, 2011, Television Business International announced that the French Group M6 has renewed its output deal with CBS, which includes Ringer.

The series has been shown in Portugal since October 2011 on pay-TV channel TV Séries under title name 'Vida Dupla' (Double Life) [131] and is available on video on demand in Sweden since March 1, 2012 on TV4 Play.