From The Perry Mason TV Show Book
Perry and Della return to the office after dinner to finish up some work and are startled to find a four-week-old baby boy in a basket on Perry's desk. Perry perceives someone to be in trouble, since he doesn't believe in storks.
Before long, the alleged mother shows up, with a trail of trouble behind her. She is arrested for murder, but not before Perry finds out that this little baby that he and Della have been caring for may be the heir to the vast Kerrick fortune.