The actor will play the titular character 'Abraham Ozler' in the movie, which has already gone on the floors.
Jayaram had played the lead in Manobala's directorial 'Naina'.
Jayaram had sported a bald look in the first part of Ponniyin Selvan.
He added that the actor's death has left a void in Malayalam cinema, which can never be filled.
The church and prayers are common themes in some of these films.
The video is an excerpt from an old interview taken when Malavika and Kalidas Jayaram were children.
Though there were rumours that the film is being dropped, the director recently rubbished the reports.
Niranjan debuted in Malayalam cinema in 'Black Butterfly' and later appeared in 'Drama', 'Sakalakalashala', 'Bobby', 'Finals' and 'Suthrakkaran'.
Malavika says she and the rest of the family always try to keep up the sense of humour that he passed on to them.
Kalidas's relationship with Tarini was confirmed when the actor posted their couple photo during a holiday in Dubai.