This Is the End to work as well as it does, and I say this as someone who has entire run out of anything except for sullen tolerance for tat least three members of its six-man lead ensemble. For anybody that can hear the name "James Franco" and not involuntarily shudder, I imagine that the film must seem even better.
For This Is the End is a powerfully self-indulgent tale of bros being bros: it stars Franco, Seth Rogen, Jonah Hill, Jay Baruchel, Danny McBride, and Craig Robinson (who, Pineapple Express notwithstanding, doesn't feel like part of the same crew as the rest, does he? Or am I just that unobservant?) as themselves, or at least parodic extensions and/or subversions of the popular impression of their persona. That on top of a mindblowing list of cameos from several of Modern Hip Comedy's best and brightest names, also playing themselves (Michael Cera's game turn as a coke fiend and general sex-addicted asshole being easily the best), in a film that, unbelievably, is at its very best when it consists of nothing but wildly specific in-jokes that, in all probability, nobody outside of the cast and crew understands down to the smallest detail. As for the places that it starts to be about the story it tells with these meta-performances of each actors' personae, well...
This Is the End never improves over its opening 10 minutes, which finds Baruchel arriving in his much-hated Los Angeles to spend some time with good old buddy Rogen, whereupon they both end up at a party at Franco's ludicrously fancy new house. Having never been terribly fond of Baruchel (though also having not gotten as deeply tired of him as I have been with Rogen, Franco, and Hill), I was not prepared for how damn good he could be in a well-appointed straight man role; he's basically the film's protagonist, and insofar as the first act's litany of excited self-reference and random name-dropping manages to work at all, it's because Baruchel makes for such a solid point of contact between the viewer and the world; we are, to a certain degree, watching the party through his eyes, and the dubious feelings he has about all the nonsense spinning around him are thus allowed to buffer the viewer from the inside baseball that might otherwise be totally intolerable and narcissistic (not that narcissism can possibly be entirely banished from a movie like this, but it's surprisingly mitigated, and there are even some genuinely nasty barbs made at Rogen and Franco's expense, though not really anybody else's).
Written by Rogen and longtime friend and writing partner Evan Goldberg - the pair of them also making their directorial debut, to uncertain effect - This Is the End relies on a lot of the exact same humor that tends to crop up in their other work, and the output of the Judd Apatow's Friends and Freaks & Geeks Colleagues filmmaking consortium generally (though Apatow's name shows up nowhere in the credits): lots of low-controversy drug humor, references to '80s and '90s pop culture, an all-consuming fascination with male genitalia. Even in the very best part of the movie, this is the bulk of what's happening, and there's only just enough character-driven observational humor to keep it afloat, if you're not the sort of person who can tolerate pot and dick jokes in more than tiny doses (and if you actively enjoy them: rock out. This Is the End was made for you). Even so, the character material is peculiarly effective: the sense of unspoken fear between Baruchel and Rogen that they don't know how to be friends anymore is even better than the same theme being played out in the Rogen/Goldberg script for Superbad, and it gives the film a solidity that serves it well as it careens through its somewhat weird plot.
That plot being: the Biblical Apocalypse. At a certain point, the party is interrupted by the End Times (the Rapture, in which all truly Christlike people are bodily removed to be with God, skips over each and every one of the partygoers), and the rest of the film consists of the only six survivors (briefly joined by Emma Watson, as herself, in survivalist mode) trying to survive until whatever help comes that's going to. There's some insightful stuff about celebrities' life in a bubble; there's even some decent end of the world humor. But the longer the film goes on - at 107 minutes, it's plainly incorrect to call it a "long" film, but it still feels awfully padded - the more it begins to wander, losing sight of anything that's even putatively comic in favor of driving its plot forward.
Weirdly, it's only once the film shifts from "let's make jokes about ourselves and people we've worked with!" to "let's make an action comedy about Revelation!" that it starts to be really self-indulgent, though only intermittently. Actually, it's only anything intermittently. Some of it is really funny, some of it is not, some of it goes from being funny to not through sheer wearying length (I am chiefly thinking of a conversation about ejaculate that goes on for what feels like 20 minutes longer than it has to). There's a downright clever parody of The Exorcist, and there are moments that honestly don't even feel like they're trying to be gags. If there's a constant, is that the film as a whole begins to ever so slowly deflate, and though some of the best moments come in the back half, the film plainly ends in a far more strained, uninspired place than it began (the last scene is just plain awful). Also, the mileage that can be gotten from "moderately famous comic actors playing themselves" ceases to pay dividends around the 40-minute mark, because really, how many ways can you make the same "James Franco is a prima donna, Jonah Hill is actually a delightful teddy bear?" joke.
God bless Rogen and Goldberg for setting up a fun time for themselves and their buddies, and for making it breezy enough that it's not very hard to enjoy it for what it is (it's always seemed that they make movies they'd like to have seen as teenagers), though I'll confess myself absolutely mystified that there are apparently people who love it. It's stretched out and there frankly aren't enough jokes in it. Nonetheless, it has fun, if hardly revolutionary things to say about the way movie actors live, and the visual effects are infinitely better than they had any particular reason to be. Always nice to have your Apocalypse look convincing.