An idiom which states an increasing amount of danger or tension, similar to "the
shit's hitting the fan" only much more terrible and apocalyptic. The phrase is partly
ironic, as if to exaggerate the rather mild (though hilarious) premise of the "Snakes on a Plane" movie starring Samuel L
Jackson, which has snakes on a plane.
"How
bad was the motorway pile-up?" "Let me tell you, it was like
snakes on a plane down there."
"How's your relationship with Chloe going?" "It's getting close to being like
snakes on a plane man, seriously." "Damn, dude."