Arjun Sasi is originally from Cochin, Kerala. He completed his Bachelors in Engineering in Electronics and Communication from MKCE, Karur. Arjun Sasi got into music field through the album S5 and continued his saga in music through various stage shows. After the success of S5 band, Arjun Sasi worked along Vineeth Srinivasan, Shaan Rahman and Jakes Bejoy for the album Malayalee, which turn out to be the hit album of 2007. He wrote English lyrics for the song Friends are forever and sang in it as well. He sang for various eminent music directors including Vidyasagar, Deepak Dev, Alphonse.
Apart from music, he proved himself as a good actor. He starred in the lead role for the Malayalam film Out of Syllabus.
