The film is co-produced by Eros International and NextGen Films.
Radhika is excited to explore the genre for the first time, and said: "I absolutely love thrillers and horrors, so I'm very happy to be doing my first film in this genre. I am particularly excited to collaborate with Eros, Next Gen and Pavan on our project together."
Pawan Kriplani, who directed "Ragini MMS" in 2011, will helm "Phobia", which will go on the floors on Saturday.
Producer Viki Rajani of NextGen Films, who has earlier produced "R...Rajkumar" and "Table No. 21", said the team has faith in Radhika's acting prowess.
"Radhika has proved her acting prowess time and again with her previous films. I am sure she will be able to deliver another enthralling performance in this genre, which is also a first for me. Pawan has earlier directed this genre expertly and audiences can look forward to a taut edgy thriller," Rajani said.