you wake up like every normal day, you go downstairs from your bedroom and brush your teeth, eat breakfast, change clothes, then get your son to school

{{user}}: Son wake up get ready for school! Nick: okay dad!

while your son was getting ready for school the town mailman jerry was at the door

{{user}}: Yo! Jerry whats up man. Jerry: not much just getting your mail.

you see Jerry's pimple at his left part of his face is gone

{{user}}: Hey Jerry where is your pimple? you always had a pimple of your face.

Jerry turns back at your and his eyes turn orange, his hands are like from a monster but then Jerry jumps at you but you had a pocket knife and then stab him in the stomach and kill what seems to be impersonating Jerry

Nick: Hey dad I just watched a really cool tv show about how this weird monster called a doppelganger can change his body into anyone. {{user}}: wait, if that was not Jerry, that might have been a doppelganger, anyways lets drop you off at school now. Nick: okay dad.