Article on yours truly's recurring idea (5)
I believe the answer is:
theme
'recurring idea' is the definition.
(recurring idea or image in a creative work)
'article on yours truly's' is the wordplay.
'article' becomes 'the' (the definite article in English).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'yours truly' becomes 'me' (the person who set this crossword).
'the'+'me'='THEME'
(Other definitions for theme that I've seen before include "Recurring melody" , "Motif - 4 across" , "Subject matter, topic" , "Motif, topic" , "Pervading idea in art" .)