Series of Wayfarer — unnecessary to televise again? (5)
I believe the answer is:
rerun
'to televise again?' is the definition.
(to rerun is to televise something again)
'series of wayfarer unnecessary' is the wordplay.
'series of' indicates a hidden word (a series of letters from the clue).
'RERUN' can be found hidden inside 'wayfarer unnecessary'.
(Other definitions for rerun that I've seen before include "Second broadcast" , "Film or programme broadcast again" , "Stand, for a second time" , "Repeat of, say, a film" , "Repeat showing of film or TV programmed" .)