Your subtitle file must match your video’s frame rate and cut. Sinister has two common versions:

Do not mix them. An unrated subtitle on a theatrical video will drift after 20 minutes.

If you downloaded a smaller YIFY/YTS compressed version of Sinister, YIFY’s official subtitle repository offers perfectly synced .srt files. They match their specific video encodes.

You downloaded the subtitle, but the words appear 2 seconds before the mouth moves. Here is how to fix it:

Using VLC:

Advanced Fix (Using Subtitle Edit software): If the drift gets worse as the movie goes on, you have a framerate mismatch. Download "Subtitle Edit" (freeware). Open your SRT, go to Timing > Change Frame Rate > Convert from 24.000 to 23.976 (or vice versa).