Mark Linn-Baker (just saw MY FAVORITE YEAR again; he was great in PERFECT STRANGERS and his guest shot on LAW AND ORDER: CRIMINAL INTENT). Amazing...and underrated...actor, I think.
Vincent D'Onofrio (LAW AND ORDER: CRIMINAL INTENT, FULL METAL JACKET, THE CELL)--he can evoke pathos and be terrifying at the same time.
James Spader (SECRETARY, BOSTON LEGAL...etc.). Much like D'Onofrio, his range is incredible. Looking forward to his new show this fall: THE BLACKLIST.
Michael J. Fox: need I even say why? Glad he's coming back to TV too.
Dwight Schultz: Murdock (A-TEAM), Barclay (STAR TREK: TNG and VOYAGER), a multitude of TV and movie guest spots...and completely believable in every single one of them.
Kate Mulgrew: after STAR TREK: VOYAGER, there was a short-lived show called THE BLACK DONNELLYS in which she played the mother of 5 adult sons. Someone else who can, I think, be 100% genuine in any role.
Jeri Ryan: post-VOYAGER, she's played a lot of attorneys, mostly, and does it WELL. I'd like to see her doing more.
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The existence of the leader who is wise
is barely known to those he leads.
He acts without unnecessary speech,
so that the people say,
'It happened of its own accord.' -Tao Te Ching, Verse 17