Yvonne received four years for conspiracy to commit murder after she hired a hit-man to kill a business rival of her husband Charlie, a London gangster.

She reveals to Yvonne that she had been sleeping with her husband, Charlie, before she got sent to prison, and later tries to attack her in the toilets with a razor blade, but Nikki Wade steps in to help.

Yvonne finds herself defending the young inmate Shaz Wiley (Lindsey Fawcett), who is left lonely and vulnerable after her girlfriend Denny Blood (Alicya Eyo) escapes from Larkhall with Shell.

She is being bullied by the recently arrived Peckham Boot Gang, consisting of Maxi Purvis (Kerry Norton), Tina O'Kane (Victoria Bush) and Al McKenzie (Pauline Campbell).

Yvonne also discovers Fenner is running brothels for wealthy madame Virginia O'Kane (Kate O'Mara) while she is in prison.

After G-Wing celebrates Nikki Wade's (Mandana Jones) successful appeal, Yvonne asks prison officer Di Barker (Tracey Wilkinson) for permission to take a bath.

When Yvonne's friend Denny returns to G-Wing, she helps them by seducing Al and recording her confession of Virginia's murder.

On the day of Barbara "Babs" Hunt's (Isabelle Amyes) wedding in the prison chapel, Yvonne makes her escape.

Fenner had earlier attacked Kris and had her sent down the block, claiming she attacked him, he had also discovered Hedges knew of Yvonne's escape plan and forced him to tell him what the plan consisted of, Fenner goes down to the hanging cell and sees that behind a cell door, the escape tunnel has been blocked off, when Yvonne goes down to the tunnel and goes through the door, Fenner appears and closes and locks the door behind her, his last words to her are "bye bye Atkins, don't bother screaming, you might wanna save on the Oxygen", realizing that the tunnel has been blocked up, Yvonne starts screaming.

Di is terrified and tells the Julies about it and on the day of Yvonne's anniversary, they request a memorial service to be held in the hanging cell for her.

Down in the hanging cell, Julie Johnston (Kika Mirylees) stabs Fenner through the throat with an icicle, causing him to drop next to the tunnel he locked Yvonne in and die.

As Fenner dies, the voice of Yvonne shouting for him to let her out from the day he locked her in the hanging cell is heard along with the gurgling sounds he makes as he bleeds to death.