In a world of immortals, everything we know or might have ever imagined means nothing. all has been tried and nothing worked. war, peace, starvation, hunger, disease are all forgotten words. they used to be entertainment for a while, until humanity realized that there's nothing left to be entertained with.
Those times are gone. immortality pulled the plug. there are no more vices, because everyone did everything. no more victims, no more pain.
There is also no more joy, no more suspense. the question 'what's next?' has lost it's meaning. we all know what's next: no matter what we do, no matter what we think, originality is out of reach. we really tried everything and did everything. nothing can surprise us anymore.
Just the same as our ancestors sought to obtain immortality, we now seek entertainment, surprise, emotion. all in vain, so far. nothing's new and will ever be and we need to cope somehow with this reality.