In Batman (1989), Joker tells his crew to get him in “5 minutes… Better make that 10.” At the 10:46:00 mark. His crew shows up at the 1:56:39 mark, almost exactly 10 minutes later.

Re-uploaded because I had to include time stamps.

The time stamp of 1:46:00 is the second that Joker is done telling his crew, and the time stamp of 1:56:39 is the first second that we can hear his crew's helicopter.