Seth Rogen
understands why someone may initially question his starring appearance in another "my friend has cancer" movie after already doing so in 2009's 'Funny People.' The thing is, Rogen's new film '50/50' -- written by Rogen's real-life friend and former 'Da Ali G Show' colleague Will Reiser -- was actually conceived first. As Rogen explains, it's nothing at all like 'Funny People.' (And he's right.)
Rogen co-stars as Kyle, best friend to Adam (Joseph Gordon-Levitt) who is diagnosed with a rare form of spinal cancer early in the film. At times funny, at times heartbreaking, '50/50' is based on Reiser's actual experiences with cancer. Moviefone spoke to Rogen and Reiser about the fine line between humor and the serious subject matter, Reiser's real-life experience with cancer, whether it's too soon for a Patrick Swayze joke (Rogen's character lists Swayze as a cancer survivor to inspire Adam) and, also, to deliver a quick message to Rogen from his former director, Kevin Smith.

Moviefone: I just finished an interview with Kevin Smith. He wanted me to tell Seth, "Hi," and, "Thank you for introducing me to marijuana."
Rogen: [Laughing] He has to get in line for that.

Reiser: Seth has done that for many people.

Rogen: Exactly. It's a lot of people's first and last weed smoking experience. I either get you started or I retire you.

Will, based on your experience with cancer, was there anything difficult for you to watch in this film?
Reiser: Is there a specific scene watching it? Yeah, I think the stuff with the mom is always the hardest. [Angelica Huston plays Adam's onscreen mom.] It's the stuff that hits home. Just the scene in the doctor's office when she tells Adam that she's going to an outreach support group for parents of children with cancer. I think that always kind of hits home and always reminds me of my relationship with my mother and what our experiences were like going through that together. But I should say that the movie is "inspired by" -- it's fictionalized. So it's not like I'm watching my real life. I think like with almost any audience member, I connect with that in a certain way.

Seth, was it weird for you knowing that you had to be funny but -- considering the content -- also conscious of where to draw the line?
Rogen: I think people who have had experience with cancer realize how -- and it's not something I really realized until Will got sick -- kind of how sensitive towards it you become when you are engaged in it. You know? It isn't a taboo subject anymore when you or your friend is living with it every day. And I think what you're willing to say about it just becomes a lot more explicit in a lot of ways. And I think we just knew that as long as we didn't feel like we were doing anything that wasn't real, we could kind of say whatever we want -- for the purposes of the characters trying to make jokes. I think that makes it OK; the character is trying to be funny -- sometimes successfully, sometimes not successfully. But I think as long as it feels like something someone would actually do, we just knew it wouldn't be offensive. You know?

Not being based 100 percent on a true story, what's the biggest difference between Adam's life and Will's life?
Reiser: Well, I did not undergo chemotherapy. It's all fictionalized. I just drew from my experience to inspire me with bits and pieces of things that happened and turned them into this movie.

Like the scene where the doctor says the word "cancer" for the first time and all of a sudden Adam zones into an echo chamber. Did that happen to you?
Reiser: Definitely. I think a lot of what the doctor said -- both the surgeon and oncologist -- was taken from real experiences, for sure. I definitely drew upon what happened and what my real experience was like for writing those scenes.

Seth, when this first came to you, did you worry at all that it was too similar to 'Funny People,' in a one sentence, "Seth Rogen has a friend who has cancer," kind of way?
Rogen: No, not at all. This movie actually existed conceptually before 'Funny People' did. And, honestly, I remember Judd telling me about 'Funny People' -- I mean, we had no idea how long '50/50' would ultimately take to get made. But it was kind of the other way around, oddly enough. I remember Judd telling me about 'Funny People' and I told him, "Well, I have this other movie that we're making with Will about what he went though." And it just seemed different enough. It seemed like they were telling different stories. Tonally they were kinda different. Scale-wise they were much different. So it really didn't bother me and it didn't bother anyone making the movies. I mean, it's not surprising that there's ultimate comparisons, but I've accepted that no matter what I do, everyone is always going to say that I'm doing the exact same thing. [laughs]

I think after people see '50/50,' no one will compare these two movies.
Rogen: OK, I hope not. But if they do!

There's a Patrick Swayze joke in '50/50.' Is it too soon for a Patrick Swayze joke?
Rogen: Oh, man, I don't know! [laughs]

Reiser: We debated that. We definitely debated it. But I think sometimes you just have to go for it.

Rogen: If you imagine, we shot that joke over a year ago. I remember saying that if people don't like this, we'll take it out. Like, we are not trying to impose this joke on people. It was not something we felt strongly about and we were like, "If people think this is funny, we'll leave it in. If not, there's a very good chance that we should not have this in the movie." But people seem to like it. It's almost an oddly cathartic joke for people in a way.

Reiser: Yeah, it never came up when we tested it or when we showed it to friends. It was always something that people laughed at.

Rogen: Yeah, to us it was scary. No one else really ever pointed it out, though.

The director, Jonathan Levine, mentioned you improvised quite a bit on set. Was there anything you improvised that you immediately said, "Wait, I was just messing around. Don't use that"?
Rogen: [Laughs] That... is a good question. I don't know! Nothing off the top of my head, to be totally honest. The character, again, is someone who is trying to be funny. You know? So you're given a certain luxury, I think, as a performer when, literally, the person who you're playing is trying to make jokes all of the time. So, I don't know. Honestly, our attitude is if it makes you think we can't do that, that's the exact thing we should be trying to do.

The scene that stood out to me the most is right after Adam has chemo for the first time and is walking out of the hospital stoned. Where did that come from?
Reiser: We initially had like a dream sequence. And it was way too expensive for us to shoot. And it involved Adam being chased by a giant, bald, fat man wearing a shirt that said, "cancer." It was really absurd. But we wanted to so something that really captured that.

Rogen: Yeah, in the script it turned into a Fellini movie for around ten minutes.

Reiser: Exactly! I wrote that when we were in pre-production and decided that we couldn't shoot that initial scene. So that was something that we all kind of sat around in our production office and just kind of just pitched ideas: Just a stoned walk and the gallows humor of it all.

Rogen: That was the first scene that our editor actually cut together. And I remember when we saw it, I remember thinking, Now that's the movie! This is what the tonal benchmark for the whole thing should be. It's funny and real and sad and somewhat audacious in how it's treating the subject matter. But at the same time it feels very honest. And I remember looking at that while we were very early in shooting and thinking, this is what we need to try to be achieving.

For Adam, the chemo treatment almost made him sicker than the actual disease. I know it was a different treatment, but what was your experience?
Reiser: Look, I was a wreck.

Rogen: Oh, yeah, Will looked really bad leading up to him finding out he got sick. I talked to Sacha Baron Cohen the other day; we were literally just talking how like when we were working on the show, every time Will would leave the office we would look at each other and be like, "There is something f*cking wrong with that guy."

Reiser: I was not in good shape. I was losing weight, I was having these horrible night sweats where I would wake up drenched. I was having dizzy spells and bad acne. It was horrible. It was not good. It was not a good time in my life. And I had convinced myself that I was diabetic because I had gone on Web MD and diagnosed myself.

Rogen: We thought it was just the stress of 'Da Ali G Show.'

Why didn't you go to the doctor?
Reiser: Because when you're that age, you're not thinking.

Rogen: I remember you started eating tons of salt. And you thought that would help you.

Reiser: I thought I was a diabetic and my mom was telling me to eat lots of salt. That's my mom's cure for everything: to eat lots of salt in everything. She thinks that's the cure. But when you're 24 years old, you don't think, Sh*t, I might have cancer. What 24-year-old do you know who talks about having cancer? Mono -- I mean, that's the worst you're going to get.

The scene most people have seen is the one where Seth's character shaves Joseph Gordon-Levitt's head. Will, did you actually shave your head and, Seth, did you feel a lot of pressure shaving Joseph's head and getting that scene right on one take?
Rogen: You didn't actually ever shave your head?

Reiser: No, never due to illness.

Rogen: Right -- just for fashion. That was literally the first day of shooting. And it's tough with a scene like that because you want it to feel real and loose, but you can really only do it one time. And we did literally improvise the entire thing -- which, in retrospect, might have been the stupidest thing we ever did.

Reiser: We sat there coming up with a list of 40 names of bald men.

Rogen: Like Michael Stipe. If we had a giant list -- please let some of these be funny. But I think we did improvise all of that stuff. I don't even know if there was dialogue for that scene in the script.

Reiser: There was some loose dialogue.

Rogen: The scene was literally written as "They shave his head." I don't think it was ever a heavily written scene.

Reiser: And that was one of the last editions to the script, too.

Rogen: Yeah, that's true. I really just thought logistically it would be way too hard for it to have him shave his head -- then we realized that we could do it.

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