Death is often just a temporary state in the magical world of Merlin.

Such is the case when Anthony Head makes a dramatic, one-episode return to the popular Syfy series this Friday, Jan. 18 at 10:00 p.m. ET/PT in an all-new episode entitled "The Death Song of Uther Pendragon".

When a stranger gives Arthur (Bradley James) the power to summon the dead, the King finds himself torn between head and heart. Unable to resist temptation, he seizes the chance to speak to the person he misses most: his father, Uther (Anthony Head). But the spirit world is a dark and dangerous place - for little does Arthur realize that his decision comes at a terrible price. Against all odds, Merlin must put right Arthur's mistake before Camelot and everything they have built is destroyed forever.

Over the first three-plus seasons of Merlin, James and Head developed a strong bond not unlike their on-screen father-son relationship. James was particularly pleased to have Head back on set for this special episode, as the actor explains below.

"It was really nice to have Tony back for a bit. I think it seemed a bit weird for him, but he fit back in, and the father-son dynamic went right back. It was good to see him, good to work with him again. I know he missed people, and I think the novelty of coming back was something he was pleased to do."

As relatively young actors when the series began, James and the rest of the core Merlin cast were perfectly balanced with the veteran presence of the savvy and sage Head and Richard Wilson, who plays Gaius. James said the two seasoned actors were always present and available to James and his castmates. Here's what Bradley James had to say about Anthony Head and Richard Wilson working together again.

"Tony didn't have quite enough time during filming the episode to emanate any pearls of wisdom, but that's the beauty of Tony and Richard - they would never force their words of wisdom on you. Everybody's got advice, everybody's got opinions, and I think it's a very respectable trait to only use them in necessary moments. Anthony and Richard are very experienced, especially from a professional, industry point of view, and they half-said things that helped me rather than going blindly into that abyss. I can't tell you how many times I've gone into a situation and thought, 'Ah, this is what Anthony and Richard were talking about.' They are great resources, and I appreciate them both."

Merlin fans will rekindle their own relationship with Anthony Head when "The Death Song of Uther Pendragon" debuts Friday, Jan. 18, at 10 p.m. ET/PT, only on Syfy.