"Seize him!" Uther shouted after glaring long and hard at the young man on his son's side, and the guards rushed in without question or second thought.

"What?!" Arthur couldn't believe his ears as he heard his father order his manservant to be caught and held; and couldn't believe his eyes when they actually rushed in and gripped the boy, dragging him off.

"Father, what is the meaning of this?!" The prince was beside himself, and after long days of captivity; in cold and hunger; his patience was really thin. More so when the guards grabbed hold of him too, so he's unable to fight them, unable to keep them from taking Merlin away.

The king glared at him as if he'd only noticed now that Arthur was present in the courtyard with the arriving knights. The man's gaze softened looking at him.

"You will thank me, my son." He said gently then turned to the other young man.

"Take him down below!" he growled.

Arthur's face paled as he incredulously stared at his father, then looked to the dark haired man.

I wasn't 'to the dungeons', or 'put him in a cell', it was 'down below'..

Merlin wasn't sure what that meant, but judging from the dread on Arthur's expression, it was something else and it was something bad.