Additional Sessions Judge S Malathi also imposed a fine of Rs 33,000.
Additional Public Prosecutor M Selvaraj said Adhi Laskmi of Kodambakkam was working as junior actress in Tamil films and had been providing financial assistance to Prabha and Edward Jayakumar in Minjur over the years.
They demanded money from her for paying rent and admitting their children in school. When she refused to give them the money, they hatched a plot to kill her.