This episode begins with a lady driver switching places with a very drunk guy. She then leaves him--and the police soon find him behind the wheel of this parked car. It turns out the car hit and killed someone--and the lady was setting up the guy for the fall. Boston Blackie gets involved when the man's attorney asks him to investigate a wildly improbable story--one where the drunk guy only can remember the dress that the lady was wearing.
This is a better than average episode of the series--mostly because there were a lot more surprises than usual in the plot. It kept me guessing and the film definitely ended up in a place I didn't expect. Not brilliant but worth seeing.
By the way, on the copy I downloaded for free at archive.org, I noticed an odd soft beeping every 10 seconds or so. Where it originated from, I have no idea.