The Woman In Black (1989)
Directed by Herbert Wise
Suggested by Reddit user _Scott_Blacula_
An undeniable classic. This film languished for years in a legal battle between the three crew members (!) that owned the rights, which may have inadvertently helped the film reach cult status. For some time the only way to see The Woman In Black was to seek it out on Usenet and download it illegally, and even then the only copies available were low-quality rips pulled from old VHS tapes (which may have added to the mystique).
THIS is how you make a great horror film with no budget and no violence. Just good writing, great performances, great direction, and a little bit of face paint.
Interesting tidbit: Adrian Rawlins, who stars in the original, went on to play Harry Potter’s father in the Harry Potter series. Daniel Radcliffe, who plays Harry Potter, went on to play the lead in the 2017 The Woman In Black remake (which you should probably just skip).