Karan (Tusshar), Tanya (Esha Deol), Tashu (Natasha), Yash (Yash Tonk), Pat (Vrijesh Hirjee), Khush (Ashay Chitre) and Dolly (Kusumati Sana) form the care free gang of college friends in Shimla all out to have fun. Lurking behind their unadulterated fun and games is a deadly psychopath who stalks them with a vengeance. An innocent attempt at saving one of their friends from what seems to them a serious offence drags them into a pit fall, the consequences of which hound them even after three years of their leaving college. A spate of murders convolutes the identity of the killer and they find it even more baffling as to who would want to exterminate them. A whodunit that doesn't let the track change to any parallel subplots or mushy melodramatic sobs, KTH isn't without its drawbacks though. Inspired by \"I Know What You Did Last Summer\", or other such teenage murder mysteries, are scripted with utmost care not to sound implausible, KTH at times tends to be less believable with an improbable twist or turn. But Tusshar, Esha, Natasha and Yash (who are familiar faces on the telly with regular appearances in numerous Balaji Telefilms' daily serials on air) acquit themselves very well in roles they did not have to do a lot of homework for.