My normal go-to for weasel-faced is Ray McKinnon, probably best known as Holly Hunter’s suitor in “O Brother, Where Art Thou?”
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I was going to say Rupert Grint because I read the OP pretty carelessly.
I remember him most from “Prison Break”, true weasel there. (I also have a friend who kind of looks like him.)
I most know him from the show “Grace Under Fire” but I did see a still from “Prison Break” that looked like a blue suit.