Similar to my other DoA Projects, I'll be doing everyone's Story Modes in order from Left to right. I will be doing Helena's Story last as you only unlock it once you beat story mode with everyone else and pretty much wraps everything up anyway. There will only be one showcase in this playthrough and that will be Nicole-458. There are couple of reasons for this, one of which will be seen once I upload her video, but the other is simply because the other characters are basically the same as they were in Dead or Alive 2 Ultimate.
I'm also going to show off the difficulty option I'm using and, yes, Normal is the "easiest" difficulty in this game, but in my honest opinion, this game's hard enough on THAT difficulty... Honestly, I'd go and say that DoA4 is the hardest game of the series, Except the original Dead or Alive game exists, and I've only ever managed to beat that game with Kasumi so... *shrug*
During the time of the fourth tournament, Kasumi caught word of the Mugen Tenshin's plan to attack DOATEC and take their revenge against the company. Worried about everyone's safety, Kasumi risked her life visiting the ouside of the village, and found Hayate. As she tried to convince him to stop the war against DOATEC, Hayate remained quiet and Ayane arrived to interrupt them, providing enough of a distraction for Hayate to leave and continue on with his mission.
Although the attack was on the go, Kasumi pursued everyone to DOATEC's TriTower headquarters so she can still stop the chaos. There, she confronted Helena Douglas, the current head of DOATEC, and begged her to leave the shinobi alone. However, Helena told her that DOATEC's lastest creation - a modifyed Kasumi Alpha, renamed Alpha-152 - was about to become active. Helena was about to shoot Kasumi, to stop her from being involved, but she was saved by Ryu, who was there helping Hayate, and Kasumi fought her way past Helena.
She then headed down to the lab to destroy Alpha-152. She fought her clone to her best efforts but in the end it appears Alpha-152 escaped in the chaos of the destruction wrought by the Mugen Tenshin invasion. After the match, having herself escaped the burning building, Kasumi is last seen watching Helena entering the blazing helipad. As Kasumi tried to stop her, Ayane prevented her from going after Helena, who by doing so saves Kasumi's life as the building starts exploding mere seconds later.