John has been given a chance to interview Tom 'Big Red' Holt - the notorious gangster (who has been in protective custody for the past 3 months). John's job is on the line, and there is only one cab in sight.
Miss that cab, and you'll miss your appointment with Big Red (and most likely lose your job).
Since a bit rides on getting in that cab, you will need to be a Target Number in order to succeed. Simply pick a cliché and roll all your dice. If you beat the target number, you succeed. Otherwise, you missed out.