Smiling Assassins

Of notice or warning there's never a trace,
For assassin's they come with a smile on their face,
At the breaking of dawn or the dead of the night,
Though you fear their arrival they're nowhere in sight,
And they've carefully crafted their art and their style,
And the only disguise they come wearing's a smile,
When they hold out their hand, kind of knocks you off track,
As you turn 'round to find there's a knife in your back,
Then the coroner ruled in an open- shutshut case,
When assassin's came wearing a smile on their face.