From The Perry Mason TV Show Book
This is another story of partners who don’t trust each other. Austin Lloyd and Dwight Garrett are partners in a reliability testing firm. But Garrett wants out when he learns that Lloyd is swindling a large aerospace company.

Faced with the dissolution of the partnership and knowing that his wife Bonnie is in love with Garrett, Lloyd plans to fake a poisoning attempt on his life, making it look as though Garrett and Bonnie tried to kill him so they could run away to Mexico. But Lloyd really does die. Perry is convinced that Garrett is innocent.