The Australian accused of conspiring with a Sydney man to behead a random stranger is a former Kings Cross bouncer and part-time actor who now recruits young men to fight with terrorist groups in the Middle East.

Mohammad Ali Baryalei is believed to be the most senior Australian member of the terrorist group Islamic State, having travelled to Syria in April last year.

Law enforcement authorities believe he has recruited at least half of the 60 Australians now fighting with Islamic State, also known as ISIL, in Iraq and Syria.

He is reported to have a trusted position in the operational command of the al-Qaeda-linked group.