The difficulty of formulating of a defence theory and the lavish celebrity trial preparation, easily afforded by the ghoulish Spector, set the context for the evolving lawyer client and person to person relationship between Spector and his understated lawyer.
Pacino, 10 pounds ham to 90 pounds real character, is tremendous as Spector, illuminating his psychic fragility, his utter whacko creepiness, his manic brilliance, his hermetic wealth, his musical accomplishment, his unwieldiness, and generally his spectacular, irresistible (partly as in you-can't-turn-away) outsizedness.
The crazy finally overwhelms the brilliant in Spector when he shows up for trial wearing a Jimi Hendrix wig, (which he claims isn't a wig.) His lawyer decides that that day she can't put him on the stand. ( I haven't been able to find out if he ever testified at either trial.)
Mamet is exceptional in extrapolating the tension from two bookends of the facts-of-the-case spectrum: the sheer outlandishness of the notion that Lana Clarkson would that particular night kill herself or even put a gun in her own mouth and the mysteriousness of the lack of blood splatter on Spector given the prosecution's theory of the case.
In that tension, within what is depicted in the film, I was left with reasonable doubt.
I thought Mirren really effective in her subdued playing of Spector's lawyer. And while Mamet initially makes a strong point of how expensive she is, we see her, payment having presumably been made, working the case agonizingly slowly, deliberately, self-questioningly, and conscientiously, all sotto voce to Spector's (via Mamet) Shakespearean, larger than life presence, a continuous mix, as noted, of brilliance and craziness.
That mix is shown particularly in the powerful scene when Spector breaks down in rage at the mock cross examination, understanding the rehearsal for what it is, as he keeps saying, while regardless of that understanding being unable to control the mock affront he perceives. In that we see what a ticking time bomb he embodies.
His lawyer's calm quieting him down, almost as if talking to a child, punctuated by Spector needing to gloat, even here, that he was right, Lennon was wrong in that particular orchestration of Lennon's record, and Spector's regaining, temporarily, his self possession are simply amazing film making, a great tribute to Pacino, Mirren and especially Mamet.
There's a lot of great meat in this film, all underlain by Spector's music and I'll be thinking about it and wanting to talk about it for some time to come.