The band changed labels in 1967, signing with CBS, recording Odessey and Oracle (the misspelling came from the artwork designers), using a Mellotron where they couldn't afford session players, then disbanded in December 1967, several months before the album was released. It sold poorly in Britain and only appeared on the US market because of Al Kooper's influence with the US label. Time of the Season became a major hit the following year but by that time the band was well and truly defunct.
In the meantime, Argent and Chris White had been working up material for a new band when they were approached by CBS, who were looking for another Zombies album. They recorded material that crept onto the market on compilation albums through the 70s and 80s, and the project appeared on a Japanese release (R.I.P.) in 2008).
Rod Argent's post-Zombies focus went into the eponymous Argent, with Chris White contributing as a non-performing songwriter. Blunstone began a solo career after a spell working for an insurance company. The others found work where they could. Interestingly, though the actual Zombies couldn't make a go of it, there were a number of fake groups touring the States under that moniker, with one of them going as far as trademarking the name after the original group allowed it to lapse.
Argent produced a hit album in 1972 with All Together Now, with the magnificent "Hold Your Head Up" (3% on the US charts, thank you very much). Blundstone's solo career wasn't quite as successful, though his distinctive vocal style has kept him in work over the years.
While suggestions they reform met with a firm refusal through the seventies and eighties, Blundstone, Grundy and White briefly reunited the band in 1990, as The Zombies, recording New World, which features guest appearances by Argent, Atkinson and an assortment of guitarists.