Final Fantasy VII: Advent Children
Voice Actor: Steve Staley
Kadaj is the embodiment of Sephiroth's hatred and rage and is the leader of the Silver Haired Man as both Loz and Yazoo appear to follow his lead. This is evident in the opening scenes as he requests that Loz and Yazoo intercept Cloud while he speaks on his phone to presumably either Rude or Reno.
After telling the person on the phone that he wishes to speak to the President, he calls Loz and Yazoo off Cloud and drives off on his bike after giving Cloud a sly grin.
Visiting The President
Shortly after Cloud leaves the Healin Lodge, they are graced with Kadaj's presence. Rude and Reno try to stop him, but they are easily defeating and Kadaj approaches Rufus seeking answers - openly admitting that he hates lies.
As he asks about the "item", Rufus says that unfortunately his operatives were careless and dropped it during the skirmish that happened in the Great Northern Crater. Kadaj informs him that they need the item for its power. The Reunion is coming and all those with the Geostigma are invited - this includes Rufus.
We Can Fight Against The Planet!
Kadaj rounds up a large group of children who suffer from Geostigma and takes them to the Forgotten Capital. He gives them a speech about how the planet hates them for what they are, but he says that "mother" has given them a special gift.
He can cure them of their affliction, but they must join together as a family and strike back at the planet! Upon saying this, he uses his immense internal powers to change the water around him. He drinks some and instructs the children to do so - which they do.
Hello Again Brother
After the ritual has taken place, a less than healthy Cloud approaches the encampment on his motorcycle. Kadaj orders some of the children to get in his way, which causes him to swerve but Cloud doesn't stop.
Kadaj informs the children that while Cloud belongs in the family along with them, unfortunately he's the black sheep in their happy flock and must be disposed of. Kadaj engages Cloud, and appears to have the upper-hand, but Vincent appears and takes Cloud to safety.
We Wish To Return Sephiroth To This Planet
As the Remnants return to Edge, Kadaj talks with Rufus once again. He informs Rufus that his theory is correct and that they are attempting to bring Sephiroth back. Kadaj seems a bit upset that "mother" chose Sephiroth over him, but her happiness is more important than his.
Shortly after, he summons Bahamut SIN to wreak havoc in Edge for his own amusement. He asks Rufus if he has any requests for the next act in the play, but Rufus doesn't seem overly amused and makes a shocking announcement.
You Had Mother All Along?!
Rufus reveals a box containing Jenova's Cells and then proceeds to throw them off the building. Kadaj is livid and after shooting a beam at Rufus (which causes him to fall off) Kadaj jumps off the building to try and get the box.
Rufus manages to shoot the box, damaging it, but Kadaj still manages to collect it and keep it from any more harm. Before he has time to inspect the damage to the box, Cloud appears and he has to make a getaway on his motorcycle.
The Resurrection of Sephiroth
Cloud manages to catch up with Kadaj and after some cat and mouse, the two eventually engage. This time, Cloud is more of a match for Kadaj and during the fight, Cloud slashes the box containing Jenova's cells in half. Kadaj then absorbs the cells into his body and transforms into Sephiroth.
As Kadaj is defeated, Cloud holds his dying body in his arms. During this time, Kadaj hears Aeris' voice calling to him. He mistakes Aeris for "mother" and when she tells him that everyone is waiting, Kadaj disappears.