The third film/television version of Alec Coppel's play, and the second to have a script by Coppel.
Conceivably, this may have been filmed to the same script as the 1948 BBC version, which was also scripted by Coppel, but in the absence of any information confirming that (and in the presence of an entirely different cast and production company), this work has been considered an entirely separate work.