If the video contains a scene you don't recognize, you can take a screenshot and use a reverse image search tool like Google Lens or Yandex Images to find its origin or other places it has been posted.
Be cautious when opening files with unusual or randomized names from untrusted sources, as MP4 containers can occasionally be used to hide malicious scripts or "steganography" in unused metadata fields. 43400grgrgngnnvrg0hrt.mp4
Where did you find this file, and is there a or detail inside it you're curious about? What is MP4 Format Video? - Tansee If the video contains a scene you don't