In July 2012, it was reported first that Suriya had signed on Lingusamy's film to be produced under the director's banner and that he would work on it after Maattrraan (2012) and Hari's Singam 2 (2013). After the completion of both movies, the actor was reported to work simultaneously with Lingusamy and director Gautham Vasudev Menon for a film titled Dhruva Natchathiram. Suriya waited for six months after Singam 2, but failed to receive a complete script from Gautham Menon and no progress took place in this period of time. Owing to this reason, he opted out of Gautham's film in October 2013 and announced that he would soon start work on Lingusamy's film. The director confirmed the news and also stated the film would officially start filming from mid-November 2013. It was said that the script had been modified a few times. The film was started without a title. In January 2014, the title was officially announced to be Anjaan. Vijay Milton was initially signed by Lingusamy as the cinematographer for the film, but in October 2013 he was replaced with Santosh Sivan, collaborating with Lingusamy for the first time. The film's editing was reported to be handled by Anthony while Rajeevan was recruited as the art director. Brinda Sarathy was confirmed to be the dialogue writer for the film.
The first look posters of the film were released on 1 May 2014. The teaser trailer of the film was launched along with the teaser of Kamal Haasan starrer Uttama Villain during the 8th Vijay Awards held on 6 July 2014 and was simultaneously uploaded to YouTube. The teaser received positive response and crossed 3 million views. Indiaglitz in its review of the teaser said, "One could see the monotony which features in all the gangster flicks, but that has been easily shadowed by the power packed cast and crew". The official trailer of the film was released on 8 August 2014 and aired on Sun Music. The trailer too received positive response and also crossed 1 million views. Behindwoods wrote in its trailer review, "Lingusamy is eyeing another blockbuster here." Indiaglitz in its review, summarised, "Overall, the trailer lives up to the expectation and it is up to the movie now." The video clip of the track "Ek Do Theen", featuring Suriya and Samantha Ruth Prabhu was released on YouTube on 10 August 2014. 2b1af7f3a8