What is the fine-grained topic of the following text: Ahead of the trailer launch, mid-day has learnt that Khan and producer Aditya Chopra have decided to introduce the principal cast — including Katrina Kaif and Fatima Sana Shaikh — by releasing a series of separate first-look posters on September 17. Only return the topic.
Release of first-look posters for Khan and Chopra's film