Vachan (Hindi: वचन, The Promise) is a 1938 costume drama Hindi film directed by Franz Osten. The regular Bombay Talkies writer, Niranjan Pal, walked out of the Bombay Talkies production team after an altercation with Himanshu Rai in 1936. Saradindu Bandyopadhyay, a famous writer known also for creating Byomkesh Bakshi, replaced Pal in the story department, writing for films like Nirmala and Vachan in 1938 and Durga in 1939. The screenplay was by Agha Jani Kashmiri, with dialogues and lyrics by J. S. Kashyap. The music was composed by Saraswati Devi aided by J. S. Kashyap. The film starred Devika Rani and Ashok Kumar, a popular pair from Bombay Talkies who worked in seven films together. Devika Rani remained the bigger star with Kumar's name being "over-shadowed" in the credit rolls, as well as the publicity of the film.Rajendranath, a popular comedian of Indian cinema, began his acting career in Vachan. The rest of the cast included Meera, Mumtaz Ali, Agha Jani, M. Nazir, Kashmiri, Maya Devi and Kamta Prasad.Devika Rani played the role of a princess in this costume drama film.