If you think about the plot too much with "Up for Murder", you'll likely see more holes and unbelievable situations than you expected. Still, despite this, it is enjoyable and a decent time-passer.
Lew Ayres plays Robert, an unbelievably naive young man who has ideas about becoming a reporter. Amazingly, with nothing to recommend him other than a perennially drunk employee, he's given a job! However, his first assignment is an odd one...to be the escort for the lady society editor at the paper. Soon, Robert is smitten with Myra (Genevieve Tobin)...to the point of being almost embarrassing. What he doesn't realize is that she's the newspaper owner's mistress...a kept woman. Everybody seems to know this but dopey Robert...and soon he's wooing her like a schoolboy with his first love. However, in the midst of this comes tragedy...and I'll say no more about that.
You just have to see this film to understand why I thought it was ridiculous. Ayres' character is just TOO naive...to the point of being, well, a bit of an idiot. And, what he later does in the film clearly confirms the idiot part! Not a bad film...but one whose plot really is tough to swallow.