WHAT IN THE WORLD IS THAT??: Four of the celebrities, from left, Danny McBride, Jay Baruchel, James Franco, and Craig Robinson, who managed to save themselves from the apocalyptic earthquake that interrupted the Hollywood party they were at, are confronted by something they have never seen before and are trying to figure out a way of escaping from it.

When Jay Baruchel was picked up at the Los Angeles airport by his close friend and fellow Canadian Seth Rogen, he was disappointed to learn that instead of unwinding, they were going to a housewarming party at James Franco’s mansion where a lot of celebrities would be in attendance. Despite having achieved his own measure of success, low-key Jay still lives in Montreal, in part to avoid such shallow Hollywood gatherings.

Upon their arrival, he awkwardly exchanges pleasantries with the host and Jonah Hill, both of whom he secretly suspects hate him. Furthermore, he’s overwhelmed to find himself surrounded by so many famous people whom he’s never seen in person before, icons that include Kevin Hart, Channing Tatum, Jason Segel, Emma Watson, and Mindy Kaling, to name a few.

Jay also feels uncomfortable about the liquor, drugs, and bawdy behavior. Such as when Craig Robinson sits down at the piano to sing a tune called “Take Your Panties Off,” while wearing a T-shirt emblazoned with the same phrase.

However, all of the above becomes irrelevant when an earthquake registering 9.7 on the Richter scale rocks the city and rips a giant fissure right in front of Franco’s place. The guests scatter in all directions as a widening sinkhole starts to swallow some of the revelers at the same time that blue beams of light lift others heavenward.

Meanwhile, James, Jay, Seth, Emily, Craig, and Jonah barricade themselves inside to await rescue. Eventually it dawns on them that the cavalry might never be coming, since what’s unfolding all across Los Angeles looks more like Judgment Day than the result of an earthquake.

Thus unfolds This Is the End, a zany apocalyptic comedy that is the directorial debut of Seth Rogen and Evan Goldberg, the writing team responsible for Superbad and Pineapple Express. This novel adventure proves to be every bit as side-splitting as their earlier work, and much of the inspired humor is due to the actors who are willing to be the butt of the joke while playing themselves.

Excellent (****). R for crude humor, coarse sexuality, graphic nudity, drug use, violence, and pervasive profanity. Running time: 107 minutes. Distributor: Columbia Pictures