This movie is one of those many movies that sounds much better than it actually is. The "death-ray by television broadcast" plot device was actually quite minor in this otherwise sub-par 'whodunit' quickie from poverty row. Overall a really poor example as I have seen much better from poverty row.
Bela Lugosi's role really isn't very interesting and he is much better when playing more bizarre characters (Murder Legendre - White Zombie, Dracula, Dr. Carruthers - The Devil Bat).