In 1981, after the breakup of PragVEC, Thirlwell started his own solo music project under the name of 'Foetus Under Glass'.

In November 1983, Foetus undertook a tour with Marc Almond, Nick Cave and Lydia Lunch in the quickly dissolved 'partnership' known as The Immaculate Consumptive.

[1] He has also appeared on albums recorded by The The, Einsturzende Neubauten, Nurse With Wound and Anne Hogan.

[1] All full-length Foetus album titles are four-letter, one-syllable words, often with multiple connotations.

[2] Beginning with Flow, the artwork of primary albums reverted to black/white/red, although other releases continue in full colour.