Zane is first introduced as a man in his late-twenties or early-thirties, who has found himself with nothing left to live for; he has no family, no money, and no girlfriend. He is first seen at a magic gemstone store where the merchant cheats him out of a good relationship with a very wealthy woman and has left him with a "junkstone" that only finds him petty change.
Zane arrived home later that day in hopes of shooting himself when he encounters Death. Instinctively, he moves the revolver from his temple and shoots Death instead of himself. It is when he meets Fate that he learns that he is now supposed to take the Office of Death.
Zane, who is living a pathetic life without money or employment. Desperate, he goes by a magic gem shop, in which he was greeted with gem stones by a merchant. He chose the Wealth stone, but trades his opportunity for romance to pay for it. He was cheated, however, for the stone he took turns out to be a junkstone, and his fated love is forever lost. Believing he has no desire or resource to cling to the world, Zane decides to take his own life.
As he pulls the trigger, he sees the specter of Death (Thanatos) advancing on him. As if a miracle, he pulls the gun from his own head and shoots Death dead. As he kills Death, he is then visited by a woman who introduces herself as Fate, who insists that Zane must become the new Death, since he who kills Death must himself become the new Death. Fate quickly explained his prime duty: to collect souls of humans who are in a balance of good and evil, which can not automatically determine their eternal destination (Heaven or Hell) without Death's personally tending to.
Ignorant of his newfound job, he struggles to find out how. From his predecessor, Zane acquires two items of Death: the Deathwatch, which counts down to the moment he must take the life of a designated "client"; and Mortis, the Death Steed, which can assume any form, ranging from a limousine, a boat, a plane, or a horse, all in pale color. The first time he collects a soul is not so smooth. In time, with his own wit and Fate's instructions, he learns about his job. Thanks to his meeting with Chronos, the Incarnation of Time, he comes to understand the use of the Deathwatch and other instruments of the office. Chronos also cares to tell him about the true nature of his office as Death, as well as the way to reach Purgatory, on which he resides.
To Zane's surprise, he discovers that his succession of the Death office was manipulated by a powerful magician, Cedric Kaftan Jr., an extremely powerful mortal magician who can command confidence and respect from other Incarnations. It was Kaftan who arranged Zane's destiny to succeed Death, and come to collect the Magician's dying soul himself. The reason for his scheme is to protect his lovely daughter, Luna Kaftan. She has been prophesied to thwart the schemes of Satan, the Incarnation of Evil, and is thus the target for the evil forces and in need of supernatural protection.
The Magician was convinced that Zane was the best for the job. He then offers Zane the love of his daughter, after having researched about him, hoping Zane would fall in love with Luna and protect her with his life. The Magician intended to die with his soul in balanced, so that he can meet Zane the new Death and give his message personally, then be taken to Purgatory without letting Satan know of his scheme.
The dead magician's plans however seem to go awry. Due to manipulation by Satan, Luna is also destined to die before she can fulfill the prophecy. The magician had used too much black magic for his soul to be in balance. In order to bring it into balance before committing suicide, he has transferred the excess evil on his soul to Luna's soul, whom he has assumed to be innocent of evil. However, Luna has a burden of evil on her soul already, and her father's scheme has put her on the course to Hell. To correct this, she volunteers to switch places with one of Death's other clients. By sacrificing her own life to save another, she manages to balance the evil on her soul.
Her actions play right into Satan's trap, who doesn't care whether she goes to Heaven or Hell, only that she dies and is no longer a threat to his plots. However, Zane has already fallen in love with Luna by this time, just like the magician had planned, and he refuses to take the soul of the woman he loves.
Now the motives behind the magician's choice of Zane are made clear to him when the other four Incarnations (Time, Fate, War, and Nature) from Purgatory approach him and explain that they were all in on the plan. The previous Death could not be manipulated into betraying the duties of his office for love, so the Incarnations decided to replace him with a young, stubborn man like Zane, who could.
Because Luna's soul is next in the queue, Zane cannot take the souls of other mortals until he deals with hers. He refuses to do so, thereby going on strike and leaving dying mortals in agony, unable to be released by death. As this is not to Satan's advantage, he first tries to bribe Zane, then intimidate him into going back to work.
Zane, however, has had a conversation with Gaea, the Incarnation of Nature, who has demonstrated to him the absolute power each Incarnation wields in its own sphere of influence. Zane eventually realizes that the office of Death is unassailable by Satan and that he cannot be harmed within the sphere of that office. As an Incarnation, Satan himself has a soul and is subject to Zane's dominion. The conflict ends in a draw and Satan has no choice but to admit defeat.
With Satan's plot exposed, Purgatory changes Luna's destiny and she is free to return to life. Zane lifts his strike, and with Luna under his protection, Satan can no longer interfere with her fate through the means of death.