article_snippet.sent: Scroll down for video .
article_snippet.sent: ITV newsreader Julie Etchingham will keep order with just one ad break during the two-hour election showdown .
article_snippet.sent: They will then be allowed to deliver an uninterrupted one-minute answer to each question, before 18 minutes of debate on each question.
article_snippet.sent: There will be just four 'substantial election questions' covered during the night.
highlights_snippet.sent: Strict rules decided who will speak and when during two-hour show .