The actress has been spotted filming alongside Michael Le Vell (who plays Kevin Webster), Simon Gregson (who plays Steve McDonald) and Joe Duttine (who plays Tim Metcalfe).
It's believed she is playing a blast from Tim's past.
Let's hope for his sake the character is nothing like the part she played in Emmerdale - stalker Sally Spode tried to sexually assault Ashley Thomas, and kill his wife Laurel!
Read more: Ryan's brutally attacked by Gary!Metro.co.uk reports that the character will arrive in Coronation Street with a connection to Tim.
She's not expected to appear on-screen until November.
We really hope she's not headed to Weatherfield in an attempt to split up Sally and Tim who, despite their mismatched characters, have proven to be one of the most popular couplings on the soap.
Perhaps she will turn out to have some connection to Tim's daughter Faye.
Or maybe she will play a part in everyone realising what a monster Tim's dad, Geoff, is.
Read more: Brooke Vincent shares last baby bump picture
He's currently chipping away at poor Yasmeen's confidence and self-esteem in a very distressing but important coercive control plot.
Whoever Sian's character is, she's sure to cause a storm!
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