Darla is the vampire responsible for turning Angel into a vampire. In other words,
she is his sire. Darla was initially featured in the premiere season of "Angel"'s
parent series, "Buffy the Vampire Slayer". She
was a member of The Master's clan, Darla actually being his favourite for 400 years.
In her early days with Angelus, Darla roamed Europe with him, terrorising others and
teaching Angelus her brutal methods. Over time, Angelus developed his own methods and
together, the two became unstoppable. However, one day, Darla brought home a gypsy
girl, whom Angelus then killed. The gypsy clan to which the girl belonged soon discovered
Angelus had killed her and then cast a spell on him, which restored his soul. Upon
making this discovery, Darla kicked him out of their house, promising that if he ever came
back, she would kill him.
Over the years, Darla joined forces with The Master and ultimately, she became his favourite
amongst what he deemed his "children". In the "Buffy" episode, "Angel", Darla became
obsessed with reverting Angel to his former self, by framing him for the attack on Buffy's
mother and by tempting Angel to kill Buffy himself. When her plan failed, Darla decided to
kill Buffy herself. As she was just about to do so, Angel staked her.
Darla has appeared in various flashback appearances throughout the first season of "Angel".
However, the biggest surprise came when Lindsey and his colleagues at Wolfram & Hart
successfully brought the vampire back to life, hoping to use the vampire as their secret
weapon against Angel.