Complex sentence: The character of 5 O'Clock Charlie returns in the Season 3 episode "There Is Nothing Like a Nurse", in which the nursing staff is evacuated based on intelligence that points to an upcoming air raid on the 4077.
Split into simpler sentences: The character of 5 O'Clock Charlie returns in the Season 3 episode "There Is Nothing Like a Nurse". In this episode, the nursing staff is evacuated based on intelligence that points to an air-based attack on the 4077.