Martha began on Prisoner as a non-speaking extra, and therefore not credited for those roles, for example, we see her leaving Doctor Miller's office after he treats her for a burn, and later we see her working in the laundry background.
Her first line was uttered while harassing Anne Yates. She is later seen agreeing to support Noeline Burke in return for a few packets of smokes. She is also involved in the storyline about Joyce Martin and the payrol robbery.
Also involved in the storyline about child murderer Bella Allbrecht, she actually murders her by drowning her in a washbasin after hearing Bella refer to Martha as stupid, sharing the same view of Martha as the rest of the prisoners, and on many occasions, Martha IS shown to be not very bright.
On arrival of inmate Toni McNally, Martha was used as muscle to take over as top dog while Bea Smith was in solitary. After the conclusion of the McNally storyline, Martha was not seen again. Her last appearance was being knocked unconscious by Bea.