Fabulous story involves English travel card? (6)
I believe the answer is:
oyster
'travel card?' is the definition.
(Oyster is a London public transport travel card)
'fabulous story involves english' is the wordplay.
'fabulous' indicates anagramming the letters.
'involves' means one lot of letters goes inside another.
'english' becomes 'e' (abbreviation).
'story' with letters rearranged gives 'oystr'.
'oystr' enclosing 'e' is 'OYSTER'.
(Other definitions for oyster that I've seen before include "Flat shellfish" , "Pearl producer" , "It produces pearls" , "Food shellfish" , "Pearl-making mollusc" .)