In a career spanning more than 60 years, Blunstone came to prominence in the mid-1960s as the lead singer of the rock band the Zombies, which released four singles that entered the Top 75 charts in the United States during the 1960s: "She's Not There", "Tell Her No", "She's Coming Home" and "Time of the Season".

Notwithstanding post-war privations, Blunstone recalled that although his family were not well-off, his parents never owning a car, they had a pleasant lifestyle in rural Hertfordshire.

Rod Argent wanted to form a band and initially asked his cousin Jim Rodford to join as a bass guitarist.

In 1968, the band broke up over management issues, shortly after completing the baroque pop classic album Odessey and Oracle.

A later album and DVD Colin Blunstone & Rod Argent of the Zombies Live at the Bloomsbury Theatre were well received,[8][9] as was their 2007 US tour.

One critic wrote, "The Zombies, still led by original keyboard wizard Rod Argent and featuring the smoked-silk vocals of Colin Blunstone, is the best 60s band still touring which doesn't have Mick Jagger as a front man".

[10] Blunstone continued to tour with Argent as the Zombies, and in April 2009 the original surviving members of the band played four reunion concerts performing Odessey and Oracle.

Blunstone and Rod Argent decided to put together a touring band, perform live and release new material as The Zombies.

And the whole process has become so organic that we're 100% happy with the Zombies name and rediscovering and playing all the old stuff and at the same time carving a new path forward which is also very, very important to us.

[12] In 2019, Blunstone was inducted into the Rock and Roll Hall of Fame as part of The Zombies, along with Argent, Atkinson (posthumously), White, and Grundy.

[1] Blunstone gained success as a solo artist in 1972 with "Say You Don't Mind"[14] (which peaked at number 15 in the UK chart and was written by future Paul McCartney and Wings member Denny Laine), and "I Don't Believe in Miracles" (which peaked at number 31 in the UK chart and written by Argent member Russ Ballard), both with string arrangements by Christopher Gunning.

He went on to appear on several albums by the Alan Parsons Project including Eye in the Sky, where he sings the hit single "Old and Wise", and Ammonia Avenue ("Dancing on a Highwire").

He continued to tour with Rod Argent as the Zombies, and the original surviving members of the band played four reunion concerts performing Odessey and Oracle, in April 2009.

His sole film part was in Bunny Lake Is Missing (1965), directed by Otto Preminger (as the Zombies) and starring Laurence Olivier.