The Kingdom of Fourland is an island nation located in the North Atlantic. The country notably holds the 52 “X” playing cards, considered to be the very origin of playing cards. These cards, each endowed with a supernatural ability, can donate their power to a qualified person, a "player". One day, the "X" cards, which were supposed to be under the protection of the government, ended up scattered all over the country, causing a lot of trouble due to the powers acquired by the people who obtained them. In secret, the King entrusted a mission to Pinochle, one of the largest companies in the nation: to find the cards to put an end to the ambient chaos. By day, Finn, Chris, Leon, Wendy and Vijay are simple employees of the car manufacturer Pinochle. At night, they are members of "High Card", a secret group made up of players whose mission is to collect the cards.