Big news! Princess in Britain was forced to ingest ecstasy and cocaine? (6,8)
I believe the answer is:
banner headline
'britain was forced to ingest ecstasy and cocaine?' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'big news princess' is the wordplay.
'big' becomes 'banner' (similar in meaning).
'news princess' becomes 'headline' (I can't explain this - if you can you should believe this answer much more).
'banner'+'headline'='BANNER HEADLINE'
'in' is the link.
Can you help me to learn more?
(Other definitions for banner headline that I've seen before include "Streamer" , "Newspaper front page item" .)