In 1973, Zajíček founded the experimental band DG 307 (named after the code for the psychiatric diagnosis that would exempt young men from compulsory military service) together with bassist Milan Hlavsa.

The band was persecuted by the communist regime, turning Zajíček (known as "Pavel Z.")

[1] After the Velvet Revolution he returned to Czechoslovakia, playing with the reformed DG 307.

Zajíček's lyrics were also used in recordings by the Plastic People of the Universe (for example "Apokalyptickej pták" from Egon Bondy's Happy Hearts Club Banned).

[4] His theater piece Pustina (The Waste Land) premiered in 2014,[5] in which he also played a major role.