In the beginning, half of them watch French star, not British (3,4,3)
I believe the answer is:
the year dot
'in the beginning half' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'them watch french star not british' is the wordplay.
'them' becomes 'th' (I am not sure about this - if you are sure you should believe this answer much more).
'watch' becomes 'eye' (eye can mean to watch or look at).
'french star' becomes 'bardot' (I've seen this in another clue).
'not' indicates named letters should be taken away.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'bardot' with 'b' removed is 'ardot'.
'th'+'eye'+'ardot'='THE YEAR DOT'
'of' is the link.
Can you help me to learn more?
(Other definitions for the year dot that I've seen before include "Time's beginning" , "As long ago as can be remembered" , "date, one imagines" , "A very long time ago" , "The beginning of time (colloq.)" .)