Why am I getting error 1118 here? - actionscript-3

Question

In the code below I have several MovieClips that are all TheBeetle(). They are in another MovieClip called gamelevel and also pushed in an array called bArray. previously I have indexed them in the gamelevel but after the event listener is called I cannot index them anymore and receive the error "1118: Implicit coercion of a value with static type Object to a possibly unrelated type flash.display:DisplayObject.". As the user clicks them, they die (and change the frame) and the dead body goes under other alive bodies, thats the reason I need to index them to 1 as they die. I understand what the error says but how can i do what i need to do?
The code works just fine but it wouldn't in the two lines i've mentioned in it, so take a look please:
public function clicked (event:MouseEvent)
{
if (event.target is TheBeetle && event.target.currentFrame <= 2)
{
var mc:Object = event.target
// TheBeetle is actually a MovieClip but i cannot write: var mc:MovieClip = event.target, if i do i receive 1118
if (mc.currentFrame == 1)
{
mc.gotoAndStop (Math.floor(Math.random() * 3 + 4));
}
else
{
mc.gotoAndStop (3);
}
mc.filters = null;
// Here i need to index the TheBeetle as i did before like gamelevel.setChildIndex(mc,1) but i'd receive 1118!
bArray.splice (bArray.indexOf(mc),1);
if (bArray.length == 0)
{
removeEventListener (Event.ENTER_FRAME,frameHandler);
waveTimer.removeEventListener (TimerEvent.TIMER_COMPLETE, changeLocation);
}
}
}

Answer 1

You need to explicitly cast target to the MovieClip Class:
var mc:MovieClip = MovieClip(event.target);
You may need to do this BEFORE the line that checks target's currentFrame, as 'Object' doesn't have a currentFrame method.

Answer 2

I would recommend to use soft casting when you work with events and targets. By soft casting, if you have catched wrong target, you will not have problems - cast process simply returns null.
public function clicked (e:MouseEvent){
var beetle: TheBeetle = e.target as TheBeetle;
if(beetle != null && beetle.currentFrame <= 2){
//Work with beetle as you want
}
}