Bill Bixby and Lou Ferrigno appeared on screen together 3 times during the run of the series. Once when Ferrigno played a body builder in the "King of the Beach". Another time was in Married (1978) during a dream sequence when Banner was trying to trap the Hulk. They also appeared together in Metamorphosis (1979), where the Hulk was tripping on acid and imagined a microphone stand to be David - Lou is clearly seen carrying Bill Bixby above his head.
This is the very first speaking role for Lou Ferrigno, at least on the screen. His partial hearing loss from a childhood infection is incorporated into his Carl Molino character.
When Mandy gives Carl a pep talk about winning the King of the Beach contest, she tells him if he wins he can go on to bigger things. She mentions Mr. West Coast, Mr. America, Mr. Olympia as possible contests he could win. Lou Ferrigno had placed 2nd and 3rd in the 1974 and 1975 Mr. Olympia contests respectively. He returned to the Mr. Olympia stage in 1992 placing a disappointing 12th and again in 1993, placing 10th.