This tool is still in development and will require a lot more features, but it currently works quite well.
You'll have to be in spectator mode or flying in creative mode for the cutscenes to work correctly. This will be done automatically in a future release.

To install the cutscene, press the download button and save the .zip file to the "datapacks" folder inside your world folder (or follow this guide).

In order to start the cutscene run the command /function cutscene-[whatever id you chose]:start.

Source code available on Github.