Marnie McDonald

 was a girl who was accidentally molecularly deconstructed by the Serapheem in Dundee, 2004.

Born in 1988 or 1989, Marnie lived alone with her father Kurt by 2004, something that led to many tensions between them.

One day, after having an argument with Kurt aged 15, the Serapheem noticed the will to get away from her and 61 other teenagers in Dundee and responded by deconstructing her molecules so she could migrate with them. However, she was unable to and was left behind, being considered missing to everyone else. DC Jana Lee and the Ninth Doctor worked together to find out the circumstances behind her vanishing, eventually using a pulse resonance chamber and the TARDIS to first talk to the Serapheem then return her to normal. After tearfully making up with her father, the two settled their differences. (AUDIO: Girl, Deconstructed)