How obtuse adult and radical ruined TV nature series (3,5,5,2)

I believe the answer is:

the world about us

'tv nature series' is the definition.
(BBC nature programme)

'how obtuse adult and radical ruined' is the wordplay.
'and' means one lot of letters go next to another.
'radical' becomes 'r' (chemistry abbreviation).
'ruined' indicates anagramming the letters.
'how'+'obtuse'+'adult'+'r'='howobtuseadultr'
'howobtuseadultr' is an anagram of 'THE WORLD ABOUT US'.

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