Seth Green’s character on Buffy the Vampire Slayer, Daniel Osbourne, was extremely underutilized and should have had a bigger role. Green debuted in the season 2’s “Inca Mummy Girl” as a guest star, before he was promoted to a series regular in season 3. Altogether, by the time he made last appearance in a dream sequence for the season 4 finale “Restless”, Oz showed up in a total of 39 episodes of Buffy. While that might seem like a lot, Oz’s character was never really given much to do outside of his relationship with Willow (Alyson Hannigan).
In real terms, only three episodes could be reasonably considered to center around Oz. Those are “Phases”, in which Green’s character is revealed to be a werewolf, “Wild at Heart”, and “New Moon Rising.” Those last two episodes served the purpose of writing off Oz’s character and, additionally, solidifying the pairing of Willow and Tara (Amber Benson). This would seem to have been by design, as writer Marti Noxon refers to these episodes as the Willow/Oz trilogy in a DVD commentary.
The shorthand reveals something deeper about the role Green served on Buffy since it indicates that his character functioned primarily to facilitate Willow’s journey. Oz was worthy of a much deeper exploration on the show and Green himself believed so as well. While it’s no secret that the actor left Buffy earlier than planned in season 4 to work on a movie, which was the 2001 crime film Knockaround Guys, it is perhaps less well-known that Green felt very limited in his portrayal of Oz.
As Seth Green explained in an interview with The AV Club, he had frequently approached series creator Joss Whedon with ideas that would add more depth to his scenes. None of them materialized and Green felt that the character's potential was being overlooked, which ultimately helped to fuel Oz’s early exit:
“There was a point at which I approached Joss and just said I was really… I felt like we hadn’t done anything that we had talked about. I felt like the character’s potential vs. what we actually were doing were in drastic opposition. And I was getting other opportunities, so I asked to be let out, because I spent an entire season as a regular on the show, not doing or saying anything. They’d bound me to a series-regular contract, yet the character didn’t really necessitate being in every episode and every scene, so I found myself forced into scenes contractually that I really had no place or role in. So I’d spend five days a week, 12 to 14 hours a day, to be in a scene with nine other people, and hopefully get to say “I think Buffy’s right!” I was like, “This isn’t what we talked about.” And I had another opportunity to do a movie, so I requested being let out for six episodes to do it, and it was just… As much as the character was peripheral, to get me off for six episodes apparently would’ve caused too much turmoil, so they just found a way to make me exit gracefully.”
It’s hard to argue with Green’s viewpoint. The main issue was likely that, between focusing on the Big Bad of any given season and fleshing out the dynamics between the four main members of the Scooby Gang (Buffy, Willow, Xander, and Giles), there was little room left for supporting characters. Oz was defined by his connection to Willow, Cordelia was mostly there to banter with Xander, and even Angel got much more memorably examined when he departed for his own spin-off. Buffy simply did not care much for mixing and matching its scene partners, as was very much evident with Oz. In spite of the real-life friendship between Green and Sarah Michelle Gellar, there are next to no meaningful interactions between Oz and Buffy. The comedic potential of Oz and Xander was severely underplayed, along with the interesting possibility of positioning Oz and Cordelia as perennial outsiders to the core four. These potentially rich dynamics were left on the table by Whedon and his creative team and they would have done a lot to develop the popular supporting cast of Buffy.
The series did admittedly get somewhat better at incorporating secondary leads into the main storylines in later seasons, even as other aspects of Buffy dropped in quality. Still, it’s a shame that Green never got to experience the narratives he’d been pushing for. Even as minimal and marginal as Oz’s screen time was, the character left quite an impression as fans loved his cool and ostensibly detached demeanor. Part of that is due to Green’s own standing in Hollywood at the time. He was already a recognizable face during his stint on Buffy, thanks to his performances in comedies like Austin Powers, and it would have made sense for Buffy to make more use of Green’s familiarity than it ultimately did.
There were rumors that Green would have joined Angel, provided the show was renewed for season 6. Those rumors have since been thoroughly debunked by Green himself, but it would have been interesting to see. More mature in its presentation, and less focused on romantic relationships, Angel would have been a good fit for Oz to make his return especially because other Buffy the Vampire Slayer characters benefitted from appearing on the spin-off.