Was there a night scene, with a house at a beach maybe, where a man (the bad guy?) opened the box...the good guy was a ways off down the beach, and there was a bright light that emanated from the house...killed the guy that opened it...or maybe killed a woman?
I seem to remember an old movie with that in it.
That was a detective movie, perhaps with the Phillip Marlow character. The plot was along the lines of Phillip searching for the box which when opened would be like a bomb with radio activity. Well, it was opened in a beach house. The End.
Don’t remember the actors but do remember the plot and the end. Will need to do a search in order to give a name.
OK the title would be
Farewell My Lovely
or
Murder My Sweet
Two different movies made from the same novel.
Info found on this sight
https://shauncostello.com/2011/03/19/the-ten-best-private-eye-movies/