We had one ALMOST like that at a convention once, except it was a CyberPunk game (listed as a CyberPunk game, and the GM denied that there were any elements of fantasy in the game) that almost immediately went down the rabbit hole into a Fantasy game, into what was perhaps intended to be a spectacle of contrasts ("lookit, MAGIC! I have a gun!") but turned out to be a game where we were basically there to absorb hit point damage while the GM's girlfriend got to save all our butts as a fairy-born cyberpunk who was returning to her world to Right Wrongs. One of us did try to commit something close to suicide (bad-mouthed the powerful enemy NPC at the diplomacy table and said, basically, "bring it"), was slain by the bad guy, and then brought back to life by the protagonists.