Role play in role playing for more role play

So a spontaneous thing just sort of happened in one of my games. Basically, the party had been wiped and had to infiltrate their way into their town that's under threat. I gave them rings that subtly changed their appearance, and the party decided to pretend to be a group of vampire hunters to hunt the hidden threat. I went along with this, and hilarity ensued. The "talker" of the group came up with an over the top persona, and the rest of them followed suit. They referred to themselves under new false names, interacted more in the town, and really brought the group together.

This type of thing can't always be forced, but if the group hasn't been role playing well, this seems like a good option to reinvigorate gameplay at your table. Give ur players the opportunity to role play as another group. If they want the ploy to work, they have to back up each other's lies, pay attention, and interact. If your group isn't prepared to be over the top, use an accompanying npc to both a role and introduce them as something odd. Use other npc's to question other characters besides the "talker", and have other npc's question them. If the group doesn't seem interested, the party's lie can make it through, they get to the goal or encounter, and let it go. But the option for it is there, and if they bite, it may really spice things up at the table and get ur players going.