According to reports today, jailed Tracy - played by Kate Ford - will be offered an early release deal later this year in exchange for extracting a confession from Gail, who is wrongly suspected of killing husband Joe.
It is believed that the plot twist begins when Gail (Helen Worth) is held on remand over Joe's death. After reaching her deal with police, Tracy is placed in a cell with the mum-of-three and starts encouraging her to open up over her predicament.
A source told The Sun: "Viewers will have forgotten how manipulative Tracy is. She'll convince Gail they need to trust each other and offers to watch her back."
In subsequent scenes, Gail will treat Tracy as a confidante - unaware that the schemer is keeping a mental note of all she says in order to twist her words when reporting back to police.
Tracy is currently serving a 15-year jail sentence for murdering lover Charlie Stubbs. Her screen comeback was announced earlier this year and Ford returned to filming on Monday.
Corrie viewers recently saw Joe (Reece Dinsdale) die in a boating accident in the Lake District as he attempted to fake his own death. However, the tragedy has left many unanswered questions and Gail will realise that she is under suspicion in episodes to air over the coming days.