The pair will appear on the BBC One daytime soap in early 2013, playing the roles of one-time lovers Carl and Lindsay.
Although Carl and Lindsay are no longer together, their paths cross again when Carl is drawn back into his criminal past.
While further storyline details have not been revealed, show bosses have promised "explosive consequences" for the pair.
A Doctors spokesperson told Digital Spy: "We at Doctors are thrilled to have worked with such high calibre young talent and hope viewers get a kick out of these cracking episodes when they transmit early next year."
Quinlan is best known for playing Gilly Roach on Hollyoaks between 2005 and 2011, while Higson portrayed Maxine Donnelly in series six and seven of Shameless.
Doctors airs weekdays at 1.45pm on BBC One.