How was it you ask? Well, you are watching it and hope that that is the end, but it just isn’t.
It’s like Seth Rogen had this idea about an apocalypse movie, but it wasn’t really a good idea, not even for a parody to which This Is The End aspires, so what was the only thing they could do to make it work? They made all the characters celebrities who play themselves at a party at James Franco’s.
And you’d think it’s funny, but the funniest moments happen at the begining and by the supporting actors Emma Watson and Michael Cerra (and Rihanna).
But it’s not like you’re gonna lose something if you watch, go ahead.
You can look at the screenshots, the plot becomes pretty obvious. Some spoilers there, perhaps.