We're expected to see the best season of Heroes ever, when the NBC series returns later this month, says stars Masi Oka and Hayden Panettiere. But there isn't going to be much Ando/Hiro bromance, and it's not only because of Hiro's terminal illness.

Talking to reporters, Oka said the cast and crew of the show are aware of the critical reactions to Heroes second and third seasons, which has in turn, made the show better for its return:

It's hard not to ride the highs and the lows of the show. Without a doubt, season one was definitely lightning in a bottle where we had something special. Season two and season three, it was hard to meet the expectations, but season four, there is some sense that our backs may be a little bit against the wall, but because of that, we're creatively swinging for the fences. There're so many bold choices and risks being made, there's a lot of creative freedom in some sense because of that. I'm really really excited about this season. I would probably say that this is as favorite a season... as season one.

Part of the reason for that, Oka explains, is the shorter length of the fourth season:

It's hard not to ride the highs and the lows of the show. Without a doubt, season one was definitely lightning in a bottle where we had something special. Season two and season three, it was hard to meet the expectations, but season four, there is some sense that our backs may be a little bit against the wall, but because of that, we're creatively swinging for the fences. There're so many bold choices and risks being made, there's a lot of creative freedom in some sense because of that. I'm really really excited about this season. I would probably say that this is as favorite a season... as season one.

This year, both Panettiere and Oka's characters will be dealing with more down-to-earth problems rather than end-of-the-world scenarios; Claire, Panettiere explained, will be dealing with college:

[My character is] in college and dealing with a new best friend and roommate. We have a very interesting relationship together, but she's really the first person that she's been able to let in on her secret and someone who's really a confidente, but that's a very delicate balance that can easily fall apart. One little misstep and her dad will bring Rene the Haitian in to wipe their memories and then that'll be that, and she's happy that she's semi-caught up to that normal life she's been chasing. Where exactly are we going to go? I think there's going to be some manipulation and some really fun stuff.

Hiro however, doesn't have much fun stuff, with the whole "terminal illness" thing he's going through - which, Oka revealed, is the result of freezing time while keeping more than just himself able to move about - which was an explanation cut from the end of the third season. But, as Panettiere herself asked, can anyone really imagine Heroes without Hiro? Well, Oka can:

[My character is] in college and dealing with a new best friend and roommate. We have a very interesting relationship together, but she's really the first person that she's been able to let in on her secret and someone who's really a confidente, but that's a very delicate balance that can easily fall apart. One little misstep and her dad will bring Rene the Haitian in to wipe their memories and then that'll be that, and she's happy that she's semi-caught up to that normal life she's been chasing. Where exactly are we going to go? I think there's going to be some manipulation and some really fun stuff.

But Hiro's ailment will be without his sidekick Ando; Oka said the bromance between the two will be affected by Ando marrying Hiro's sister in the first episode of the new season, which was something that came as a surprise to Panettiere. Then again, maybe sh was just waiting to watch the episodes herself:

Because I was working so much last season, I Tivoed all the episodes so I could watch them back to back to back, and I could not put my remote down. "Just one more episode! Please!" And this is a show that I'm on, and I don't generally like to watch myself. But it's exciting, and it's smart, and I don't think it belittles the audience, and I think it's just one of those rad shows.

Shen then checked herself, and asked, "Did I really just say that? Did I really just say 'rad show'?"

Well, Heroes, the most rad show ever, returns September 21st.

[via io9]