The actor, who played Josh Ashworth on Channel 4's teen soap, takes on the role of suspicious character Jez Field in next Monday's episode of the BBC medical drama.
Jez's storyline begins when his grandfather Fred pays a visit to his doctor Daniel Granger (Matthew Chambers) and asks for a repeat prescription of painkillers.
Later, Fred makes a return visit and claims to have lost his prescription, meaning that a reluctant Daniel is forced to print out another one. However, events take a twist when a pharmacist calls Daniel to report that two identical prescriptions have been brought in for 'F Field'.
Following the discovery, Daniel heads out to quiz Fred but his suspicions are soon directed at Jez when he spots him hanging around outside The Mill.
Pictured: Sonny Flood as Jez Field.
When Daniel decides that Jez must be stealing prescriptions for his own purposes, he confronts him and a group of his dodgy-looking friends - leading to a showdown. However, whether Jez really has done anything wrong remains to be seen.
Flood starred on Hollyoaks for nearly five years, but his character was written out of the soap in mid-2010 as part of a shake-up instigated by then-producer Paul Marquess.
Doctors airs weekdays at 1.45pm on BBC One.
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