En 1989, alors que sa 3ème année dans le soap s'achevait, Thom Bierdz a vécu une terrible tragédie personnelle : sa mère bien-aimée a été assassinée par son jeune fils, Troy, souffrant de schizophrénie paranoïaque. Initially Paul was a "bad boy", who had a romance with Nikki Newman (Melody Thomas Scott), giving her an STD.
While Paul and business partner Andy Richards (Steven Ford) work undercover to infiltrate organized crime, he dates prostitute Cindy Lake. His mother opposes his relationship with Cindy, and also disapproves Paul's marriage to Lauren Fenmore (Tracey Bregman).
Their union suffers when she is stalked by Shawn Garrett (Grant Cramer), who convinces Paul that Shawn and Lauren had an affair.
The affair produced Paul's son Ricky Williams (Pete Porte); Isabella was admitted to a mental institution and Ricky grew up away from his father.
Years later, Paul established a relationship with his daughter Heather, who returned to Genoa City (now an adult) as a lawyer.
The romance ends when she takes up with Greg Foster (Wings Hauser); Paul begins dating April Stevens (Cynthia Eilbacher), who gives birth to his daughter Heather (Eden Riegel) despite his desire for her to terminate the pregnancy.