|The first in this series titled 'Oru CBI Diary Kurippu' was released in 1988 and it turned out to be one of the biggest grossers then. This provided Madhu the impetus to come out with Jagratha (1989), Sethurama Iyer CBI (2004), and Nerariyan CBI (2005).
Incidentally, in all these films Mammootty plays the role of a CBI officer Sethurama Iyer, who cracks complicated murder cases in all the four films with ease, but not without leaving the audience on the edge of their seats.
The background score of the film became quite popular, and years after the release of the first two sequels, became popular as mobile phone ringtones. All the sequels use the same background score, composed by music director Shyam.
'The rest of the cast and all other details will be decided at a later stage because at the moment, we are looking into the completion of the script,' said Madhu.