Narrative tenses are used to describe events that happened in the past, and for telling stories.
http://www.bbc.co.uk/learningenglish/english/course/intermediate/unit-20/session-2/activity-3
http://www.bbc.co.uk/learningenglish/english/course/upper-intermediate/unit-26/session-1
The past perfect continuous, had + been + present participle, describes an action which started in the past and continued up to another point in the past.
http://www.bbc.co.uk/learningenglish/english/course/intermediate/unit-14/session-2/activity-3