New HBO series "The Leftovers" aired its second episode last night to mixed reviews. Although the episode's ratings have not yet been released, many have called the series "disappointing."

Rolling Stone magazine accused the show's producers of being complacent, and lamented that episode two, titled "Penguin One, Us Zero," was predictable. Several bloggers found the series confusing, while others enjoyed that the show poses more questions than answers.

The drama follows the lives of people in a fictional New York town who are left behind after their loved ones disappear. The cause for the disappearance is unknown, although the series' premise is similar to "Left Behind" – a series of novels about the rapture that were adapted into a film trilogy.

"The Leftovers" does not have a faith-based approach, however. Some children and pastors remain while other, more unsavory characters, have been taken in the "Sudden Departure." Families are splintered, and mankind becomes increasingly carnal. "The Leftovers" provides the images that viewers expect to see and have seen in other rapture-inspired films, and some have criticized that the series does not take enough risks.

"The Leftovers takes place in a well-trod genre, in a form, the postmillennial prestige drama, that's been analyzed like few before it," Rolling Stone said in a review of last night's episode. "The more it stops doing the things it has to do and starts doing the things it wants to do, the better."

They also called the series "reheated," in a Twitter post.

Last week's premiere was mediocre, drawing only 1.8 million viewers. Mic Network called the drama "the most disappointing show of the summer," and described the show as having darkness but no depth.

"Every frame is an exercise in pain, either physical or emotional, and it is exhausting," Mic wrote.

"With a show so far built on concept and plot, rather than character, that pain is also blunt and indiscriminate. Other than pain for pain's sake, the show's task at this point is to make clear why we should care enough to put ourselves through it."

Despite the criticism, "The Leftovers" received a 65 percent approval rating on Rotten Tomatoes, and was called "the best 'Twilight Zone' episode you never saw" by horror guru Stephen King.

With eight more episodes to go in the first season, there is plenty of time for "The Leftovers" to live up to King's proclamation.

"The Leftovers" airs Sundays at 10 p.m. ET on HBO.