Close encounter of the odd kind

After an unusually long and productive drift dive we reached our safety stop. As you do on all safety stops, my dive buddy and I decided to "practice" what it felt like to experience an out of air scenario in a controlled environment and in the presence of two instructors and a Dive Master.

Just when I reached 0 bar and began to notice a significant drop in tank pressure these two characters showed up, from nowhere, unannounced and on cue. One to my left and one to my right:

Again I was certain the gauntlet had been thrown down. No guesses as to who would be running out of air first.