Sylvia, played by Stephanie Cole, whips up her own "space cakes" after purchasing drugs from a local dealer, according to the Daily Star.
The outspoken café worker is hoping to combat the pains of old age, and ends up sharing the 'treats' with a handful of her friends including Dennis Tanner (Philip Lowrie).
However, an argument later erupts when Sylvia's son Roy Cropper accidentally sells a batch to Rita Sullivan and Norris Cole. Keen to make sure they don't eat the cakes, Sylvia is forced to confess all.
Upon discovering Sylvia and Dennis's antics, Rita is quoted as saying: "How many others? My God, it's a flaming drug den in here. Sylvia, you were trying to get him addicted. She's no better than a pusher."
Sylvia replies: "I will not be vilified for attempting to relieve the suffering of my friends. I broke the law and I would do it again."
Coronation Street fans will see the storyline begin next month.
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