This episode brought back the voice of David Graham after his voice wasn't heard in Scarlet and Joe 90. (But I'm not sure about David's voice in Joe 90.)

Captain Blue -- er -- Joe, sorry, gives the Prince the bomb part he has made for him and questions the Prince about his use for it only when he places it in the teddy bear. So, if the Prince had placed it in a normal looking bomb that would have been ok with Joe? Shouldn't he have questioned it's use BEFORE he agreed to sell it to the Prince?

That scene in the king's bedroom, with Matthew standing nonchalantly on a chair, made Matthew look quite a bit bigger than he usually does when he's been shrunk down.

Why didn't Father Unwin mention that assassination attempt to the king? Did the hotel personnel quietly tidy away the mess down on the ground and say nothing to anyone about it?

Is it standard operating procedure, when talking down an amateur flying a plane, to have him (or her) abort the first attempt and come around again? It sure happens a lot.