An "opening cutscene" refers to a short video or animation that plays at the beginning of a video game or movie to introduce the story or set the scene. Full definition
For only $ 4.99, players will be able to bring a friend along to beat up tons of 1980's gangster thugs who decide to punch your girlfriend and kidnap her (also has one of the most memorable opening cutscenes of all video game history). (co-optimus.com)
New opening cutscene to Chapter 5 Festival type side - quests added to Chapter 10 (they're terrible) Chapter 14 Grandeur expansion (novacrystallis.com)
Would I have to restart from scratch and keep rewatching the entire opening cutscene until I beat the chase sequence without dying? (kotaku.com)