Raised in Dundee with her brothers and sisters, Medea did her best to be the best at everything until she became a teenager. Suddenly she was a total wild child! She had a zillion piercings ... she had purple hair ... she had no hair at all. Her father was completely disappointed in her when she dropped out of school at sixteen and moved in with a bass player in Glasgow before leaving him for a performance artist in London. But eventually Medea grew up and simmered down. She and Andrew hadn't spoken in years and she wasn't about to move back into his home while she cleaned herself up so instead she and Percy shared a house and so the elder two MacTavish lived and trained together for the next few years.

Medea and Percy came into contact with Los Vigilantes de la Noche and their Council but didn't like the way they did things, and so the MacTavish continued to work alone as they have for the last half millenia.

Medea is the thinker of the siblings. She and Percy balance each other out very nicely that way. He is the fighter, and she is the planner. She loves her other sisters and Hadrian, though she and Echo tend to butt heads sometimes simply because they are so much alike. She trys to take care of Siren as she is still growing up, and tries to lead her away from the paths that she herself took when she was her young sister's age.

The MacTavish family moved to New York five years ago to help in Arnand's fight against the vampires of the city and they have found a second home within the Forty. She had a very brief relationship with Arnand Jacobs that resulted in their daughter Alice MacTavish, whom Medea cares for herself. The couple broke up soon after their daughter was born but they are still good friends as well as comrads in arms and Medea has no problem with Arnand as a person or a father figure to their daughter.

Medea MacTavish is a striking woman in her mid thirties. She's a tall highlander, like her siblings, with amazing eyes and a strong gaze. Her hair is naturally a dirty brown, but she prefers it red ... though sometimes she will go blonde or black to match Percy.