lead-in
From Longman Dictionary of Contemporary EnglishRelated topics: Television & radiolead-inlead-in /ˈliːd ɪn/ noun [countable] AMTINTRODUCEremarks made by someone to introduce a radio or television showExamples from the Corpuslead-in• The last sentence in a paragraph should form a lead-in to what is to be discussed in the next paragraph.• Station A and station B both have excellent lead-ins.• I may be able to get a good lead-in shot before we even arrive at the hacienda.• This is why the best news program may not have ratings as high as a news program with a strong lead-in.• The lead-in to a news item should only take a few seconds.