Rishi (Rakesh Galebhe) and his girlfriend Adithi (Poojitha Kuraparthi) set out on a journey by road to visit Rishi's father and their car breaks down en route. A stranger (Bhargava Poludasu) offers them a stay at his house and as their stay extends Rishi gets nightmares and the stranger behaves freakishly. With each passing moment there are startling twists and many dots between Rishi's past and the stranger get connected which leaves the couple shell-shocked. What is Rishi's connection with the stranger and how does he and his girlfriend come out of the weird situation is the story of Gatham.