When an American fitness club opens a branch in Korea under corporate pressure, a new manager comes with it. With a wonderful, distracting new figure, Manager Jenny has the attention of all of her staff.
Florist Ae-ran and forensics investigator Min-ho from the Public Prosecutor's Office both have a family that everyone wants. However, Min-ho can't handle bed time so Ae-ran starts a 'challenge game' in which she seduces and has sex with strange men. One day, Ae-ran and Min-ho meet Alex at a tango cafe. Alex is interested in Ae-ran and approaches her while Ae-ran takes interest in Alex who is more handsome than her husband. Min-ho later witnesses them in action and gets angry when he finds out the man Ae-ran seduced is Alex. Min-ho feels nervous because he finds out Alex isn't just a game partner and approached him for a reason. Min-ho tries to get rid of Alex but Alex chokes Ae-ran and Min-ho even more and feels catharsis. The game they started is turning into a catastrophe...
4 old friends gathered after a long time. Banal daily conversation and continuous smut as always. Their sexual bluff battle start with such as, ‘You never held hands of an Idol’, ‘A common point of magpies and congress members – repay favors with their own body.’ and ‘I’ve slept with… nonhuman.’ At last the final chapter of the bluff battle comes. ‘Guys, do you believe in UFO?’