Christopher Colquhoun is set to make his debut on EastEnders later this summer.

The Royal Academy of Dramatic Art trained actor, 56, is best known for appearing in shows including Casualty, Holby City, Coronation Street, Vera, Absentia and Fleabag.

He will now also appear in EastEnders, playing Darnell Larson Jr, Denise Fox’s half-brother.

The BBC has teased that the Fox-Truemans are “left reeling when Kim makes a shocking discovery”, uncovering a half-brother of Denise’s that she never knew existed.

However their introduction is far from straightforward, and for Darnell, “what begins as an unexpected family reunion soon takes on a different significance when he learns of Denise’s cancer diagnosis and her ongoing treatment”.

Colquhoun said: “I am thrilled to be finally moving to Walford after all these years, and the welcome I’ve received has been phenomenal.

“Hearing I’d got the role was an absolute doof doof moment for me… hopefully there’ll be plenty more of those to come!”

Frempong, who previously appeared in Too Much and Essex Girls, added: “I am extremely excited to be joining EastEnders! I have watched the show for as long as I can remember and have such vivid memories of gathering around the TV with my family, especially at Christmas, to watch all the drama unfolding on the Square, so it feels pretty surreal to now be a part of the action!

“I’m really looking forward to working with, and learning from my new colleagues, whom I’ve long admired, and hope audiences enjoy getting to know Grace and all the complexities she’ll bring to their screens!”

The show’s executive producer Ben Wadey said that Kim’s discovery uncovered a new branch of the family and the cast and crew were “excited to introduce viewers to new members of their extended family”.

He added: “It’s been great to delve into this wider family network, and we’re delighted to welcome Christopher and Krysstina to the cast as we bring two new faces to Walford.”