Marcy is a teenaged Caucasian, with long, blonde hair and a slim figure. Her outfit consists of a red t-shirt that exposes her navel, blue jeans tied in a brown belt, and brown shoes.
Marcy flirted with Fred Jones on sight, which made Daphne Blake jealous. To make matters worse, she was also catty to Daphne; when Daphne said she saw something terrible in the window, Marcy suggested she just saw her own reflection. She also rudely called Daphne, "Daisy" and then "Debbie".
She was born on Halloween and grew to resent the holiday because it interfered with celebrating her birthday. She built the Scarecrow Robots and created the holographic projection of the Ghost of Hank Banning to ruin Halloween for the others, which was why she took an engineering class.
What's New, Scooby-Doo?
Marcy had been elected the Corn Princess of the Halloween ball. But on Halloween night, she was caught controlling robot scarecrows to scare everyone and ruin Halloween because it upstaged her birthday every year (which her parents felt guilty about). But since no one got hurt, the police have her make up for what she did by doing community service. She winks at Fred as she was taken away, telling him when she'll be out.
Marcy: Yep, I'm 18. Able to legally... vote.
Marcy: Oh, Blondie? I'll be out in 300 hours.
- Marcy indicates to Fred that she still wants him once her community service is over, but Fred obviously isn't interested and leaves with the rest of the gang the next day.