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Arijit Singh's debut song in Hindi cinema was "Phir Mohabbat," which was featured in the 2013 film "Murder 2." The song, composed by Mithoon and written by Kumaar, became an instant hit and established Singh as a promising vocalist in the industry. With its soulful melody and Singh's emotive rendition, "Phir Mohabbat" showcased his exceptional vocal abilities and paved the way for his successful career in Bollywood music.