If I had to choose my “most underrated middlebrow filmmaker,” it would definitely be Jim Sheridan, whose work I’ve admired for a long time (up to and including 2009’s fine Brothers.) One of his coups was to cast Postlethwaite in In the Name of the Father, resulting in him damn near stealing the movie from Daniel Day-Lewis. R.I.P.
Update by Rob: This is my favorite Posthelwaite:
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