If the incidents around you are happening faster than your heart beats then very moment jolts you... The moment might be of happiness, Shock or despair. In "Achanak" Arjun's (Govinda's) cause of happiness is his loveable father, brother (Rahul Roy), Sister-in-law (Farha), brother-in-law (DilipTahil) and a family lawyer Sagar (PareshRawal) who masterminds their prospering business. Arjun's happiness is doubled when he meets his love Pooja (Manisha) and when the love blossoms, Arjun's heart beats double but it almost comes to a stop when danger lurks in the form of an attempt on Arjun and Pooja's life. They are saved but in afreak incident Arjun's brother gets killed by his wife Madhu (Farha) and Arjun's love becomes the convict and how?... That is what gives a sudden jolt to the story as well as to Arjun. Arjun's problem is compounded when he helps Pooja to escape from jail. But he cannot escape from his family responsibilities as his father gets killed brutally and he has to solve the mystery carefully because the mystery is shrouded in his near and dear ones... Now Arjun and Pooja have to play the ultimate game to expose evils and in the process the protagosists became the victim of the police... like the proverbial phoenix our protagosistsrise and how! Songs, thrills action emotions is what makes Achanak always one step ahead of what people presume and at the end nobody can say they had assumed the things... Anytime, anything can happen... Achanak.
(From the official press booklet)