Mortal Kombat 4 is 1 vs 1 fighting game, similar to the other Mortal Kombat games, but this is first game in series with 3D characters models. The player can choose from 15 different fighters at the start (and several unlockables later on). Many fighters from earlier games in the series make a comeback (like Scorpion, Sub Zero, Liu Kang, Sonya Blade, Johnny Cage etc.) while other new fighters join in, like Shinook (who is the main evil character in this game), Fujin, Jarek, and Kai. Goro returns as a boss.

Thousands of years before the setting of the first game, Shinnok, one of the Elder Gods who control the six realms in the Mortal Kombat universe, attempted to become the conqueror of them all. Thunder god Raiden fought and defeated Shinnok in a war that spanned hundreds of years, sending him to the Netherrealm, where he would be trapped forever. Now, Shinnok has managed to escape from the Netherealm with help from the sorcerer Quan Chi, and seeks vengeance against the Elder Gods who banished him. In his plan, he first conquers the realm of Edenia, with the aid of a traitor, Tanya, while he prepares to attack the Elder Gods. In order to stop Shinnok's menace, Raiden requests help from the Earthrealm warriors who saved the realms from Emperor Shao Kahn in previous titles.