Engine off and then just ignore everyone.
years ago when I worked in a hotel we hired a coach to go to Birmingham for a 'It's a knockout' day
We got to the service station and when we returned the coach driver had turned the engine off and the lights off and closed all the doors and just sat there. we are knocking and he ignored us. then he got out and sat on the curb.
Apparently as we had been drinking he was upset and now decided enough was enough. We had to bribe him with several items from the service station.