The 28-year-old - who recently filmed guest spots for BBC One's Casualty and ITV1's The Bill - will play shady Letherbridge drug dealer Brett Sullivan.
Despite his outgoing demeanor, witty humour and undeniable charm, his true persona is that of a thuggish drug dealer, driven purely by money. His canny planning, however, is not to be undermined and while he serves as the brains of his operations, he enlists the help of others to serve as his brawn.
Speaking of his role, Sloane, who played unstable Niall Rafferty in Hollyoaks - told DS: "Brett's a great character - he's a cocky Scouse drug dealer driven by cash. It's been great filming with Doctors. It's probably the fastest thing I've ever filmed!
"I thought Hollyoaks was quick, but the number of scenes they film in a day at Doctors is immense!"
He jokingly added: "I think I've exhausted all the guest parts now for about three years! I'll need a regular part after the play in the New Year!"
The episode, titled 'Bleeding', is due to air in March.
Sloane will appear alongside The Office and Pirates Of The Caribbean actor Mackenzie Crook in Jerusalem as it transfers to the West End's Apollo theatre from January 28.
The original run of the Jez Butterworth play - in which Sloane plays bearded country hardman Troy Whitworth - played at the Royal Court Theate earlier this year.
Sloane is due to become a father in March.