Characters of Sachiin Joshi and Nargis Fakhri arrive at a big haveli (mansion) on a weekend holiday. There's something eerie about this place from the word go, and Joshi begins to get nightmares and experience a weird presence. There's even a creepy looking (read: unintentionally funny) caretaker, who throws in bits of wisdom about the return of an old spirit.
This is one of the most cliched plots for a horror fick, and director Bhushan Patel goes back to the old school haunted haveli stories [apart from several Ramsay films, Raaz (2002) and 1921 (2018) are the more recent examples] for inspiration. If there is a twist to the stereotypical horror story, the trailer doesn't give any hints.
The director spells out, through Mona Singh's character, how a ghost who has come back to fulfill its desire or seek revenge is a dangerous one. Haven't we heard this umpteen times before? Singh also points out in the end, in case you were still wondering about the film's title, that the spirit becomes super powerful on amavas (new moon night).
Amavas seems like a rejigged version of the haveli-based horror films that Hindi cinema has produced many times before.
Watch Amavas trailer below: