Dhinarathrangal (transl. Days and Nights) is a 1988 Indian Malayalam-language film written by Dennis Joseph, directed by Joshi and produced by S. V. Krishna Reddy and starring Mammootty, Sumalatha and Mukesh.^[1] The score and soundtrack were composed by Shyam. The film was inspired by the Hindi film Achanak (1973).

• Mammootty as Aravindan
• Sumalatha as Dr. Savithri
• Mukesh as Ajayan
• Parvathy as Treesa
• Siddique as Farm Labourer
• Prathapachandran as Doctor
• Devan as Unni
• Karamana Janardanan Nair as Sankarath Madhava Menon
• Babu Namboothiri as Thomachan
• Rohini as Ponni
• Philomina as Aravindan's Mother
• Sukumari as Lakshmi
• Jose Prakash as Commissioner Unnithan
• Jagannatha Varma as Madhava Menon's Brother-in-law
• Vijayaraghavan as Sasi
• Ganesh Kumar
• Mohan Jose
• Azeez as Minister
• Baiju as Biju
• Santha Devi as Naniyamma
• Jagannathan
• Kunchan as Hospital Attendant

The film was released on 21 January 1988.

There is only one song in the film, "Thirunellikkadu Poothu". It was written by Shibu Chakravarthy, composed by Ouseppachan and sung by M. G. Sreekumar and K. S. Chithra. The song features Mukesh and Parvathy.^[3]