Georgia Lester, who has written for the E4 teen drama since its second series, told DS that the cast and crew were impressed with his acting.
"He is playing the school counsellor. Am I allowed to tell you that?! He's very funny. From what I've heard on set, everyone came away saying how amazing he was," she said.
"He's got some really funny quirks and he bonds a lot with one of our main characters, and helps that character at a time in need."
Pauline Quirke has also been confirmed as a guest star on the fourth series, which begins January on E4.
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