Scenario: two FLV files sitting on Flash Media Server 2.

My .swf file uses FLVPlayback to play video files on FMS2 using rmtp protocol.

What's the simplest way of playing the second video right after the first
video at the end?

N/M, I found the answer from the following URL:
http://www.actionscript.org/forums/showthread.php3?t=89557

To quote that URL:

for anyone who cares:

FLVPlayback.stopped
Availability
Flash Player 8.

Edition
Flash Professional 8.

Usage
var listenerObject:Object = new Object();
listenerObject.stopped = function(eventObject:Object):Void {
// insert event-handling code here
};
my_FLVplybk.addEventListener("stopped", listenerObject);


/* So your flv component on the stage would have an instance name of
my_FLVplybk. Then the code would go on the actions layer above the component
keyframe (or atleast in a position where the instance name already or actually
exists so the code can refer to it). /*