Biff is a construction worker on Sesame Street who speaks with a gruff New York accent. His partner is Sully. Biff first appeared in Season 5, and made periodic appearances through Season 25. He is married to a woman named Ethel.
Biff often asks for Sully's opinion, but interrupts him before Sully gets a chance to even make a sound. He also tends to ask him questions and then eggs Sully on by repeating, "Huh? Huh? Huh?", a reference to a routine by comedy duo Burns and Schreiber. As performer Jerry Nelson said in an interview, "Sully wasn't so much Schreiber, but Biff was the Jack Burns character." Biff often has trouble figuring out how to perform various tasks, and by the time he's figured it out, Sully has already finished it.
Biff has a niece named Roxy Marie. According to Episode 2608, he also has four kids, one of whom is the infant Mary-Biff.
He has sung songs such as "We Coulda", "Think of Your Fingers", "This Song is For the Birds", and appeared in "Do De Rubber Duck". He also appeared with Judy Collins in the song "One Thing Leads to Another", and with Johnny Cash in "Five Feet High and Rising".