The film starts out with a cloaked stranger entering a medieval insane asylum, all about his form is a whitish-gray cloak that obscures his physical form from us, though he is human.  He carries a staff in hand and walks with a purposeful stride that is somehow both determined and aloof.  He is shown the door to a cell by another, unknown man, and is led inside.  There is a figure on the floor, the gnarled figure of an old and haggard man whose features are slack and eyes haunted by torment and insanity.  When he sees the stranger he reacts violently, trying to scramble away as fast as he can.

Then Marius looks up to the stranger and sees what he really is, or what Marius thinks he really is.  The stranger becomes suffused in light and glory, powerful wings spreading from behind his back as gossamer strings of light.  The stranger speaks to Marius, telling him how hard it was to find him, as if he were hiding from everyone as well.  Then Marius recounts how he meet the Wanderer (the Hero who Diablo is contained within) at the Citadel of the Sisters of the Sightless Eye, and how he fled that destruction.  It fades into a series of flashbacks within a flashback, further testament to Marius´s sad state.

Marius recounts of how he fled the horror of the Rogue´s Encampment to an opium den in the forests, where he could drown away his troubles in drinks and drugs.  However, as he sits in one corner in a drug-induced stupor, the horror and terror he had for so long fled from follows him, that terror is the Wanderer, the hero from the events of the previous Diablo, the Hero now locked into conflict with the raging essence of the Lord of Terror.  He drags with him a huge sword that he can no longer carry, using it as a cane to carry him from place to place.  Although not much is seen of the Wanderer´s face, the misery of his existence permeates everything.

Unforunately for the patrons of this Opium den, the Wanderer is soon overcome by Diablo´s spirit, he goes into a rage, flipping over a table in the process.  One of the girsly patrons of the den laughs as the Wanderer does this, but this soul isn´t destined to laugh for long.  A greenish mist begins to flow from the Wanderer´s body, and horrors begin to occur as the entire den is gripped in the magic of the Greater Evil known as Diablo.  Skeletons appear in a cyclone of flame and slug-like demons erupt from the floor, running amok and killing all of the den´s patrons except the terrified Marius.

The Wanderer beckons Marius from amidst the flames Diablo´s magic has caused, motioning for Marius to follow him on his rampage of destruction throughout the lands.  Marius does not follow, apparently, but he knows that his destiny is now irrevocably linked with the of the Wanderer.  The 5-minute cinematic leaves many questions unanswered, many of them important questions.  In the stranger how comes to Marius in his cell really the powerful Archangel Tyrael, or he is only a hallucination from Marius´s fevered delusions.  He could just as well be the Wanderer and Marius wouldn´t know, though many think otherwise.

"Who then shall be saved?"