Anyway, who is Casey Siermaszko? Here is in a few roles from the eighties, you'll remember him.
He played 3-D, one of the members of Biff's gang in Back To The Future (and Back To The Future Part II). He, of course, was the guy always wearing 3-D glasses, so clever nickname there.
There he is all the way over the right.
He was a part of another gang in 1986. He played Billy Tessio, Vern's older brother, and friend to Eyeball Chambers in Stand By Me.
There he is, all the way to the left
1987 was a big year for Casey. He had what looks like his first starring role in a major motion picture and what has become sort of a cult classic. He plays Jerry Mitchell, the dork who runs afoul of the school bully and is challenged to a fight after school. Its a teenage High Noon, appropriately titled, Three O'Clock High.
1988 was also a big year. Nothing where he carried a movie, but he was in a movie with Matthew Broderick and Christopher Walken, Biloxi Blues. As per usual, with Casey, here is he is peering over Christopher Walken's shoulder.
And, last, but certainly not least, in 1988, he played Charles "Charlie" Bowdre as a part of Billy The Kid's gang in Young Guns.
He's the one to the right of Emilio Estevez, with the beard.