Anne Griffin was a former inmate of Wentworth Detention Centre.
Anne was a seemingly meek, timid young woman sent to Wentworth Detention Centre for robbing a shopkeeper at knife-point. Anne insists that she is innocent, and that the money found on her when she was arrested was loaned to her by her friend Megan, however, no trace (or even proof of existence) can be found of Megan and so with no alibi, Anne is to await trial.
Soon after Anne's arrival, Bea is attacked from behind in the corridor, and it eventually emerges that Anne was responsible (not liking Bea's authority over the other inmates). Bea plans her revenge but Judy persuades her to hold off, convincing her that Anne is mentally unwell.
Anne tries to convince the authorities that Megan has written to her, giving her the alibi she needs, but it turns out that Anne wrote the letter herself. As Erica realizes that Anne needs psychiatric help, various details come to light about Anne's abusive upbringing, her imaginary friend Megan, and the baby she had (also called Megan) that later died, which has left Anne in a very confused state.
Anne is inside during the big tunnel escape plan at the end of the 1980 season; after the other woman realize Anne is unreliable, they try to cover up all proof of the escape plans, telling her it was merely a prank, in fear that she might inform the officers.
Things come to a head during the escape attempt (165); Judy, Mouse, Doreen and Irene Neagle make their escape, but Lizzie decides at the last minute to join Doreen, leading both her down into the tunnels, and Bea after her trying to call her back. As the tunnels collapse, trapping Bea, Lizzie and the injured Doreen, Anne deliberately covers the cover to the tunnel (with a "grave" for Megan) to stop them from getting out, leaving them trapped in the collapsed tunnel for several days.
Anne won't hand over the photos of Elizabeth to Chrissie claiming that they are of Megan. Bea arrives to carry out her threat just as Chrissie attacks Anne herself. She is later found to be mentally unbalanced and transferred to a psychiatric hospital before Bea would have had her revenge on Anne.