Stellenbosch is from South Africa, and was Dr. Grief's second in command in the South African Bureau of State Security (BOSS). She called these "happy days". Stellenbosch loved torture, and she would work out with weights every morning for an hour just to keep her muscles in shape. It is stated that her favourite method of interrogation is burning the victim with a cigar.
Stellenbosch was in charge of looking after and rearing Dr. Grief's "offspring", his clones - including Julius Grief. Stellenbosch was given the job of school administrator, and she was akin to a mother-figure to the clones; yet she never really felt any compassion for them, seeing them as a means to an end to achieve her and her master's goal of global apartheid.
Stellenbosch was also vice principal of the academy, with her duties including greeting new "students."
She met Alex Rider this way, and took him from Yorkshire, where he had been stationed by MI6, down to France, and then to a hotel in Paris where she secretly took Alex down to the basement for dinner, and evaluated him, observing his every move. She now knew everything she needed to know about Alex, for Julius to imitate.
Stellenbosch took Alex to Point Blanc Academy and introduced him to Dr. Grief himself. Grief said Alex was rude and disappointing and he would improve him.
Stellenbosch was next seen when Alex found a locked secret door in the academy and set off every alarm in the school. Guards ran up, punched a code, and stopped the noise. She appeared and barked at Alex for intruding, and said the toilets were downstairs when he lied about it.
Stellenbosch dragged James Sprintz, Alex's only real friend in the academy, downstairs to the library in the middle of the night one night, and Alex was shocked to see James back in his bed, sitting up as if nothing had happened when he returned. Stellenbosch then got alerted thanks to microphones in the cells, that allowed her and Grief to eavesdrop on the captive children. She found out Alex was an agent of Mi6, and that he was there to shut the school down. When Alex raced out of the cells, promising to come back with MI6 and free the children, Eva Stellenbosch was ominously standing outside the cell doors. She ruthlessly backhanded Alex, almost breaking his neck and knocking him out cold. She then took him to Grief to be interrogated. Eva then interrogated him with Dr. Grief, then locked him up overnight for dissection the next day.
Alex desperately escaped and Eva and Dr. Grief were furious at being woken and sent assassins down to kill Alex.
However Alex survived, only just, and returned to the academy with MI6 agents, and broke in. Eva Stellenbosch went mad with anger and hatred, and barged into the dining hall to fight Alex, and almost killed him, but Wolf, an MI6 soldier, broke in, gunned down Eva, but she shot him before she was sent hurtling out of a window, dead, thanks to the force of Wolf's gunfire.