Superb acting in "Seance on a Wet Afternoon"

I recently found this movie on the Turner Classic Movies channel, and was totally blown away by the acting of Kim Stanley and Richard Attenborough.

I'll apologize for the embedded trailer, which was the best of the few that I could locate.  The trailer is from 1964, is overly long with too much plot detail, intrusive music, and some terminal unnecessary hyperbole.

But I can't find any faults with the movie itself.  TLDR: Kim Stanley has Richard Attenborough kidnap a young girl, with the intention that they will reveal clues about the girls disappearance and location in seances, thus promoting the woman's career as a psychic.  But the woman is clearly deranged, and the girl's well-being is endangered.

The buildup of dramatic tension is so intense that I actually took a break during the movie to walk around and "chill" a bit.  Kim Stanley gives one of the best performances I have ever watched; she was a nominee for Best Actress at the 1965 Academy Awards, but lost that honor to (for fox ache) Julie Andrews (Mary Poppins).  Seance on a Wet Afternoon was nominated for four BAFTAs (Stanley, Attenborough [won], screenplay and cinematography).

JustWatch does not list the movie as streaming for free anywhere; you will need to access it via TCM or a library copy, or perhaps on YouTube.

Addendum:  Reader Rick found the full-length movie online in the Internet Archive.  It is clickable to fullscreen.