[Warning: This story contains spoilers from the season-four finale of AMC's The Walking Dead.]

Fresh off its bloody and deadly season finale, AMC's The Walking Dead has promoted three for its fifth run.

Alanna Masterson (Tara), Christian Serratos (Rosita) and new arrival Andrew J. West (Gareth) have been upped to series regulars for season five of the zombie drama, The Hollywood Reporter has learned.

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Masterson made her debut on the drama from showrunner Scott M. Gimple in November, playing Tara, one of the women The Governor (David Morrissey) encounters after the fall of Woodbury. She has become loyal to Glenn (Steven Yeun) after she lost her family and watched as The Governor executed Hershel (Scott Wilson). (The show's Tara is not to be confused with the comics character of the same name.)

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Serratos, meanwhile, plays Rosita, an iconic character from the comics created by series executive producer Robert Kirkman. She made her debut in the second half of season four in November as a member of Abraham's (series regular Michael Cudlitz) Army supporting his mission to bring Eugene (series regular Josh McDermitt) to Washington, D.C. She signed on to Walking Dead in September with a recurring role and option to be a regular in season five.

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For his part, West made his debut during Sunday's season-four finale as Gareth, the head of the group living at Terminus -- the so-called "sanctuary for all" -- who may or may not be overseeing a group of cannibals. THR exclusively reported that the Greek alum signed on to the series in November with an option to be a regular in season five and that the character would have a big presence and play an important character on the series. (And he certainly did: Gareth currently has nearly everyone trapped at Terminus in one of the show's most dramatic cliffhangers yet.)

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"Seeing Gareth and Rick and the people of Terminus and our survivors go head-to-head is going to be interesting," exec producer/comics creator Robert Kirkman told THR. "There is a very deep, dark and storied history to Terminus and how these people came to be that will be revealed in season five."

Masterson is repped by LB Talent Agency, Masterson Management and Abrams Artists. Serratos (Twilight) is with Global Artists Agency, Thruline and Stone Meyer. West is with ICM Partners and John Pierce at The Group.

Their promotions comes nearly a year after The Walking Dead promoted Chad L. Coleman (Tyreese), Sonequa Martin-Green (Sasha) and Emily Kinney (Beth) to regulars for season four. This season, the series also added Cudlitz and McDermitt as well as Lawrence Gilliard Jr. (Bob) as regulars.

Email: Lesley.Goldberg@THR.com

Twitter: @Snoodit