The original unaired pilot for Full House starred John Posey as Danny Tanner. Here's why he was replaced by Bob Saget for the rest of the show.

Long-time fans of the sitcom Full House may find it hard to imagine anyone other than Bob Saget in the role of Danny Tanner, but the original pilot for the show starred actor John Posey as the Tanner children's dad. The unaired pilot is almost identical to the pilot that ended up on TV, with the notable exception of Danny looking rather different.

Unfortunately for Posey, he was the second choice to play Danny from the start. Full House's executive producers - Jeff Franklin, Thomas L. Miller and Robert L. Boyett - had previously worked with Saget on the show Bosom Buddies, where he had done warm-up for the studio audience. Miller then saw Saget in the Richard Pryor comedy film Critical Condition, and felt that he would be right for the role of Danny Tanner. There was a snag, however: Saget had already signed up for a CBS morning program called... The Morning Program.

Posey was cast as Danny Tanner after a representative from ABC saw his comedy show, Comedia, in Atlanta. Speaking in an interview with Yahoo! TV Posey recalled, "They... pulled me aside and said, 'Hey, we'd like to see you get in front of our comedy development people'... I went ahead and went [to Los Angeles]. And then of course the pilot they gave me right away was Full House." He admitted that at the time he was an inexperienced actor, and in particular was unfamiliar with the kind of comedy required for a fatherly role in a sitcom. "[I had been] doing Saturday Night Live-type, Second City comedy, very physical comedy," Posey explained. "And Full House was very, you know, sweet and different."

The recasting of Danny Tanner had more to do with the sudden availability of Saget than any actual failings on Posey's part. The Morning Program was canceled after just nine months on the air, leaving the Full House execs' first choice for the role of Danny free in time for them to shoot a new pilot. Posey said that losing the job came as a shock to him: "Nobody said there were problems. It seemed like everything was fine. We shot it. I learned as much as I could in a short period of time. And next thing I know... 'Hey, you're no longer employed.'" The young actresses who played the older Tanner girls - particularly Candace Cameron Bure, who played D.J. Tanner - were also upset, having bonded with Posey during the filming of the pilot.

Full House ran for eight seasons on ABC and was recently revived on Netflix in the sequel series Fuller House, which follows an adult D.J. Tanner as the widowed mother of three children. After leaving Full House, Posey wrote and starred in a one-man show called Father, Son and Holy Coach, and went on to have a steady career as an actor and writer. And while he may not have been chosen as one of the all-time great sitcom dads, he did go on to star alongside his real-life son, Tyler Posey, in the MTV series Teen Wolf.

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