In the original film, Stefan is portrayed as a humble figure, loving father, and a more forceful side of the kingdom's monarchy consisting of himself and his wife, Leah. When confronted by Maleficent, he remained silent, mostly, but with a stern, and fairly intimidating expression. Aside from that scene, Stefan is mostly seen as a soft-spoken man; specifically during his scenes with the more boastful King Hubert (Stefan's closest friend).
This version of Stefan is very brutal, hateful, tyrannical, power-hungry, paranoid and obsessed with killing Maleficent, to the point where he did not care about seeing his dying queen.
At a young age, Stefan has always been ambitious. He couldn't bring himself to kill Maleficent at first because of their past friendship, but his desire for the throne led him to betray her anyway. The consequence of this betrayal was severe; he painfully cut off and stole Maleficent's wings, which ultimately turned her to evil, as she vengefully retaliates by cursing Aurora as the baby out of rage once she learns this.
His hatred was spawned from his guilt for stealing her wings, in fear that she would take her revenge upon him; this is seen when Maleficent curses Aurora while he helplessly watches. Stefan indeed shows his remorse over his past betrayal and begs Maleficent not to kill Aurora, in which Maleficent responded by having Aurora having death-like sleep instead of actual death. Unfortunately, because of his paranoia and guilt for his crime against his old friend, combined with Maleficent's act of revenge by cursing Aurora, Stefan's sheer hatred for Maleficent proved too great, even greater than Maleficent's own hatred against him. This was shown at the climax where he sadistically taunts and torture Maleficent as soon as she enters his castle and undoes Aurora's curse (though he may never learn this). Therefore, whatever friendship and love that he had with Maleficent, ultimately dies as he tries to stab her from behind, leading to his own death.
King Stefan and Queen Leah are the monarchs of a Kingdom. He is overjoyed when his wife gives birth to a baby girl whom they name Aurora. The whole kingdom was invited by Stefan to celebrate her birth. But his and his queen's happiness is short lived, as the evil fairy Maleficent, the only person not invited to Aurora's celebration, enters his castle and curses the baby. She then prophecies that on Aurora's sixteenth birthday, she will die from pricking her finger on the spindle of a spinning wheel. After she leaves, one of the Three Good Fairies, Merryweather, weakens the curse so their daughter will sleep instead of die. The King and Queen make the hardest decision of their lives: their daughter must be raised by the Three Good Fairies away in the forest in order to protect her. King Stefan ordered all spinning wheels in the kingdom to be burned in an attempt to prevent the curse from happening. The narrator reveals that sixteen sad and lonely years passed for Stefan and his dear queen.
Sixteen years later, he is waiting for his now teenage daughter's return to the Castle. While in the dining room drinking, he and Hubert quarrel over their children until Hubert mistakenly grabs a fish instead of his sword and they burst out laughing. When Aurora pricks her finger on the spindle, the Good Fairies put everyone in the Kingdom to sleep. When Maleficent is defeated by Prince Phillip, he awakens and finally meets his daughter.
In the short segment, Stefan, Leah, Hubert, and Phillip all go off on a royal ceremony where Hubert is due to give a speech. Trusting their daughter, Stefan and Leah give Aurora the "keys to the kingdom" while they're away.
King Stefan appears in the feature film Maleficent portrayed by Sharlto Copley. In contrast to the character seen in Sleeping Beauty, this version of Stefan is the main antagonist of the film and has quite a history with Maleficent making her a victimized villain.
As a child, he was an orphan and often stole things. He first met Maleficent when he escaped to the Moors after stealing a gem. The two became the best of friends and on Maleficent's sixteenth birthday, Stefan gave her true love's kiss as their close friendship gradually blossomed into romance. However, one night, Stefan stole Maleficent's wings so he could lie that he killed her and become the new king. He married King Henry's daughter Princess Lelia and together they had a child of their own, a baby girl they named Aurora.
However, his treacherous actions would cost him dearly as Maleficent placed a dark curse of eternal slumber upon his daughter Aurora as revenge for what he did to her. Over the next sixteen years, Stefan became extremely paranoid and obsessed with hunting Maleficent down, so obsessed that he couldn't care less for his dying queen.
When Aurora returns on the day before her sixteenth birthday, he has her locked up, but when the curse starts, she finds her way to the dungeons where the spinning wheels were burnt and pricks her finger, putting her into her deep slumber.
Stefan and his guards capture Maleficent and Diaval. Stefan brutally tortures Maleficent and taunts her. However, just when he's about to kill her with his sword, Maleficent's wings return to her, thanks to the help of Aurora. He is quickly overpowered by Maleficent and is carried onto a tower by the fairy. Maleficent beats Stefan and nearly strangles him, but decides to spare him. Blinded by his overwhelming pride and seething rage, Stefan refuses defeat and attacks her again. The two fall from the tower, but Maleficent manages to become airborne, while Stefan plummets to his death, ending his venomous wrath forever.
After Maleficent curses Briar Rose into an eternal sleep, her victory falls short when King Stefan awakens the cursed maiden with true love's kiss. He and Briar Rose later marry, presiding over their kingdom in a palace, and have a daughter named Aurora. Maleficent, on the other hand, becomes dejected since her revenge is spoiled and loses her ability to turn into a dragon. Years later, Aurora is set to marry Prince Phillip, and in a bid to restore Maleficent to her former glory, Regina tries motivating her into getting vengeance on Briar Rose's daughter. Fearing the former dragon will harm Aurora, King Stefan and his soldiers arrive at the ruined portion of land that Maleficent once scorched with her flames decades ago. When they begin arresting her, Maleficent attempts to transform, but it fails, leaving both her and Regina to be captured for execution. As the women are tied and forced to walk, Regina burns her own binds and hurls a fireball at the men before her magic dries out. Luckily, Maleficent morphs into a dragon, and as she swoops down from the air, King Stefan shouts for his guards to retreat. With a well-aimed breath of fire, she shoots it at the king, who manages to block with his shield. Later, when Maleficent confronts Aurora, she reveals she did not kill King Stefan in order to make him suffer and see his precious daughter be cursed as her mother was.