I was home in St. Louis on furlough when I received a telegram -- "Leave cancelled, return to base immediately." And I did. 

Oooh, bad telegram...

The closest to that I ever came was when another fireman and I were fishing on Lake Ray Hubbard, just past the outskirts of Dallas. We watched a thin column of black smoke at the downtown skyline turn into a huge column of black smoke. Once you start to see white mixed in with the black smoke that usually means they're getting water on it - the white is steam. We watched it grow for 30 minutes and still saw no white so we ran to the closest marina and called the fire department switchboard. After the first, second, third, fourth and fifth alarm on a fire, the next call is a signal 1-7 which includes calling in all the off-duty personnel. The fire only went to four alarms and the dispatcher told us to go back to fishing...