Johnson was an Indian film score composer and music director who has given music to some of the most important motion pictures of Malayalam cinema, including those for Namukku Parkkan Munthiri Thoppukal, Oru Minnaminunginte Nurunguvettam, Vadakkunokkiyantram, Perumthachan, Amaram, Njan Gandharvan, Ponthan Mada, and Bhoothakkannadi.

He was noted for his lyrical and expressive melodies together with simple but rich tonal compositions of thematic music. Johnson is a recipient of National Film Awards twice and Kerala State Film Awards five times. He started his career as an assistant to G. Devarajan in 1970s and debuted as an independent composer in late seventies with Aaravam. He was a recurrent collaborator for directors Padmarajan, Bharathan, Sathyan Anthikkad, TV Chandran, Kamal, Lohithadas, Balachandra Menon and Mohan. He has composed music for more than 300 Malayalam films, the most by any composer except for Devarajan.

Johnson began his independent career by composing the film scores of Bharathan’s Aaravam (1978), Thakara (1980) and Chamaram (1980). He composed his first soundtracks for the film Inaye Thedi, debut film of director turned still photographer Antony Eastman and actress Silk Smitha. It was Devarajan himself, who suggested Johnson to the director. Then came Bharathan’s Parvathi and Balachandra Menon’s Premageethangal. Premageethangal was a notable success with four of its songs - “Swapnam Verumoru Swapnam”, “Nee Nirayoo Jeevanil”, “Muthum Mudipponnum” and “Kalakalamozhi” attaining cult status.

He came to prominence through his collaboration with Malayalam author and director Padmarajan. Koodevide was their first venture, which had one of the most famous songs of Johnson “Aadivaa Kaatte”, a pathbreaking song in Malayalam music history. It was one of the first songs in Malayalam to have a grant orchestral score and the song was born out of Padmarajan’s need for a western song for his innovative film. Song composition took place in Woodland’s Hotel, Chennai.

Another notable feature of this song was the lyrics by O. N. V. Kurup, who for the first time wrote lyrics for a pre-composed song. Johnson worked for 17 films with Padmarajan, including his last film Njan Gandharvan. This productive collaboration saw the detailed screenplay and cinematography of Padmarajan become a fertile ground for expressive musical narration and thematic scores for Johnson. This is seen in some of the greatest motion pictures of Malayalam cinema, like Namukku Parkkan Munthiri Thoppukal (1986), Oru Minnaminunginte Nurunguvettam (1987), Nombarathipoovu (1987) and Perumthachan (1990). Another notable collaboration of Johnson was with director Sathyan Anthikkad, with whom he associated in almost 25 films. He was able to provide some of his most popular songs with Anthikkad and this combo is widely accepted to be one of the greatest director-composer collaborations in Malayalam cinema. Acclaimed Malayalam director Bharathan also collabrated with him in multiple films including Parvathy, Palangal, Ormakkayi, Kattathe Kilikkoodu, Ente Upasana, Oru Minnaminunginte Nurunguvettam, Ozhivukalam, Malootty, Chamayam and Churam. His major other collaborations with directors include Mohan (Oru Katha Oru Nunakkatha, Sakshyam, Pakshe and Angane Oru Avadhikkalathu), Sibi Malayil (Kireedam, Chenkol, Dasaratham and Nee Varuvolam), Sreenivasan (Vadakkunokkiyantram andChinthavishtayaya Shyamala), Lohithadas (Bhoothakkannadi and Arayannangalude Veedu), Kamal (Peruvannapurathe Visheshangal,Shubhayathra, Ee Puzhayum Kadannu and Paavam Paavam Rajakumaran), and Balachandra Menon (Shesham Kazhchayil, Premageethangal, Kilukilukkam and Kelkatha Shabdam).

Johnson won the National Film Award for Best Background Score for the films Ponthan Mada (1994) and Sukrutham (1995).[9] Johnson is the only composer to receive this rarely given award twice. He was the first Malayalee music composer to receive an award in music category and is also the only Malayalee music director who received two national awards in music category. He has received three Kerala State Film Award for Best Music Director, for the films Ormakkayi (1982), Vadakkunokkiyantram and Mazhavil Kavadi (1989), and Angane Oru Avadhikkalathu (1999). He was awarded the Kerala State Film Award for Best Background Music for the films Sadayam (1992) and Sallapam(1996). He has thus received five Kerala State Film Awards in music category, an achievement he shares with Devarajan. He has received the Kerala Film Critics Awards four times, the most recent in 2008 for Gulmohar.

In 2007, he won the Mathruboomi Award for Best Music Director for Photographer (2006).[10] He won the Mullasserry Raju Music Award for the song “Enthe Kannanu Karuppu Niram”, also from the same film. In addition, he has received numerous other awards and nominations including Devarajan Master Memorial Award and Raveendran Master Memorial Award.[11] In addition, he has received numerous other awards and nominations including Devarajan Master Memorial Award and Raveendran Master Memorial Award. He died at Chennai on August 18, 2011 due to a heart attack.