Good-cop-bad-cop

When he and his partner play good-cop-bad-cop, I bet I know who plays bad-cop.

Source: wiktionary

They played "good-cop-bad-cop", they skipped questions and repeated questions, they went over the same ground three and four times, they pointed out natural causes for things he had witnessed, they asked what his real motives were to get his adrenalin pumping, they called him "imaginative", and calmed him down when he took offense, and at the end of two hours both they and Prophet were exhausted.

Source: wiktionary

He played good-cop-bad-cop all by himself. First he was tender and considerate, worrying that she might have cut her hand, and the next instant he was berating her for a supposedly faulty memory where her own marriage was concerned.

Source: wiktionary

You just have to be really strong and if the actor starts to bitch, you say, ‘Okay’ and you play good-cop-bad-cop, and you bring in the other head producer.

Source: wiktionary