After Cui Qishan agreed with Liu Jinghui's plan, he didn't report to Tao Lu, and went directly to find the office manager. He then casually visited several Criminal Police Squad offices and called some colleagues from departments like the Public Security Brigade along the way.
The police's undercover agents, informers, and sources are clearly distinguished. Among them, undercover agents are the most prestigious, rarely seen in ordinary cases. Informers and sources can be official or unofficial; the use of the former is quite strict, so they are generally disliked.
More often than not, police officers who have been on the job for a while naturally get to know some fringe figures, exchange a few phone numbers, and can ask around if needed.
Some officers even skip the step of exchanging phone numbers, selecting some particularly unintelligent targets—there really are such people, and they're not hard to find, just keep a close eye on them.
