The actress will soon appear in the role of tragic would-be mother Laura Mowbray, a character who kicks off an intense new storyline for the BBC One daytime drama.
Doctors fans will be introduced to Laura on Thursday, November 1, when she arrives at Letherbridge police station with her husband Colin (Steve Money) to report a missing child.
The couple are clearly shaken as they fear for the safety of baby Sofia, a little girl they were trying to adopt.
However, show regular Doctor Jimmi Clay (Adrian Lewis Morgan) and DCI Driver (Elizabeth Rider) soon learn that the adoption wasn't as legitimate as it first seemed.
Further storyline details have not been disclosed, although show bosses have confirmed that Jimmi and Driver's discovery will "open up a shocking new investigation that threatens to shake some of Doctors' most loved characters to the core".
Best known for her role as Mandy Dingle on Emmerdale, Riley is one of 14 celebrities taking part in the new series of Strictly, which launches its live shows tonight (October 5).