、。
When dinner ends, there's going to be a movie announcement.
Literal
Dinner [subject-が] end-[conditional-と], movie-of announcement [subject-が] exist-[polite-ます].
The inflight/cruise-ship style of announcement. ~と here is the automatic-consequence conditional: 'when X [regularly, as scheduled], Y.' アナウンス is a katakana loanword from English 'announce' — here 'announcement,' though in Japanese it gets treated as a full noun. Stock phrase for public schedules.