Vernacular for a whole bunch of fucks all gathered together in a cluster, so as to properly overwhelm you when you least expect it. In fact, the surprise element is an essential component of this phenomenon.
Unsurprisingly, a clusterfuck generally precedes a meltdown, which may be conceptual, partial or total. Said meltdown may or may not be obvious to observers, but it is always there nonetheless, at least to some degree.
Note: Some shit in life you just can’t avoid.
P.S. – If no one dies consider the outcome successful.