Take my opinion with a pinch of salt because this was the first version I really got to know and Jon Vickers has always seemed such a completely plausible Grimes with his strength, anger, desperation, isolation and paranoia - he sounds like he could kill with a single inadvertent strike. The story goes, of course, that Britten hated it, preferring Peter Pears' version. There's so much I admire about Pear's' roles for Britten but it's Vickers for me here.
Elsewhere Heather Harper is a wonderfully warm Ellen Orford and is supported by an excellent ensemble. Colin Davis can be expansive at times but the fire and rage of Act One leaves me breathless. No matter how many versions I hear I always come back to this one. After over thirty years it istill sounds thrilling.