Competition missing Tango – Strictly's biggest character quits (5)
I believe the answer is:
evens
'quits' is the definition.
(as in 'call it quits')
'competition missing tango' is the wordplay.
'competition' becomes 'events' (I've seen this before).
'missing' is a deletion indicator.
'tango' becomes 'T' (phonetic alphabet: alpha, bravo, charlie etc.).
'events' with 't' removed is 'EVENS'.
'strictly's biggest character' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for evens that I've seen before include "square" , "Balanced odds" , "less likely than 27 [ODDS-ON]" , "Odds offering equal chance of win or lose" , "50:50 probability" .)