LEIGH SALES, PRESENTER: When one of Australia's favourite comedy groups the Doug Anthony All Stars broke up in the mid-1990s, the founding member, Tim Ferguson, didn't tell his bandmates that he'd been diagnosed with multiple sclerosis. It's now 20 years on and Ferguson's in a wheelchair, starring in a Doug's reunion show at the Melbourne Comedy Festival. Paul "Flacco" Livingston is in Richard Fidler's place as the guitarist, and as Libbi Gorr reveals, the Doug Anthony All Stars are still provoking the same outrage and hilarity.

LIBBI GORR, REPORTER: The Doug Anthony All stars, Australia's iconic bad boy comedy cabaret trio of the late-'80s and '90s are back in town, reuniting for two shows this weekend in Melbourne's Comedy Festival.

If you look closely at this, though, ...

(Footage of Doug Anthony All Stars performance shown)

... you'll notice two big differences. This man (Tim Ferguson) is in a wheelchair with MS. And this man (Paul Livingston) was once this man:

PAUL "FLACCO" LIVINGSTON, PERFORMER (archive footage): Oh, you couldn't scratch yourself.

LIBBI GORR: Who has replaced this man (Richard Fidler) who is now this man and very busy with a real job.

The man in the red jacket (Paul McDermott) is the same.

So how is it going to work?

PAUL MCDERMOTT, PERFORMER: Well we've got to put the brakes on first. 'Cause we're on an incline. He'd get away from us if we're not careful.

LIBBI GORR: They started as buskers on the streets of Canberra and now they're back on the streets to launch the festival.

PAUL MCDERMOTT: We've never done it with Tim in the chair though and the last time we busked was probably, what?, 20-odd years ago.

TIM FERGUSON, PERFORMER: Help!

PAUL MCDERMOTT: See, nothing happens. ...

... Oh, come on, this fella's in a god damn chair, people. What are we thinking about?

LIBBI GORR: But the new Doug Anthony All Stars are all about their feelings.

PAUL "FLACCO" LIVINGSTON: That's where he talks about it, when he's on stage. He'll take 'em right to the edge of their mortality.

LIBBI GORR: Is that where he can only talk about it?

PAUL "FLACCO" LIVINGSTON: Mm. Time is short and you got to hurry and that's a big part of this show. We are temporary people, especially the people on stage.

LIBBI GORR: Are you telling me that you're doing this for him?

PAUL MCDERMOTT: Oh, I hate that. I hate that ...

LIBBI GORR: Are you telling me ... ?

PAUL MCDERMOTT: No, I wouldn't say that on camera. I get a lot out of it myself. You know, I enjoy it. I've always loved it, so ...

LIBBI GORR: You've always loved him.

PAUL MCDERMOTT: Yeah. It's gone in and out, that relationship.

PAUL "FLACCO" LIVINGSTON: Paul's got two switches. He's a taciturn teetotaller who just sits there and says nothing or he's the raconteur who's absolutely charming and roguish, but I've never found the middle bit of Mr McDermott. Maybe there's no middle bit.

TIM FERGUSON: His solid gold, his job is to be gruff and nasty and short, which he does the third one very well.

PAUL MCDERMOTT: Stay with the man in the chair, stay with the man in the chair. This is where it's happening. Come on Tim, pick up the pace.

TIM FERGUSON: (Adopting German accent) Mein Fuhrer, I can walk!

LIBBI GORR: This is the real story of the Doug Anthony All Stars, circa 2016, coming to terms with life's fortunes.

PAUL MCDERMOTT: I don't think anything really prepares you for - for the magnitude of it. I don't know if I'm - I don't know if I'm still comfortable with it. it's - I find Tim incredibly - you know, he's gracious and he's - he's heroic in many ways. He'd probably hate me saying that. I think it's best to try and just find the person again, scrape away all the bits and pieces that seem to be blocking your vision from just seeing that person.

TIM FERGUSON: A lot of people will say, "Mmm, oh, well, ooh, be careful, be careful saying that," and, "You can't say that these days." For Christ's sake, you just say it, you know, and if something comes back, well you just deny saying it. I don't mind calling myself a spastic cripple because technically, as far as the dictionary's concerned, it's true. Laughing about something makes you higher than the thing. It puts you above whatever it is that's scaring you.

LIBBI GORR: And regrets, he's had a few.

TIM FERGUSON: Back then, all I thought was, "I can't walk on stage and limp like this. What if this stays? It's over!" Whereas if I'd been smart, I just would have gotten in a wheelchair.

PAUL "FLACCO" LIVINGSTON: He didn't tell me. I think Paul told me. I don't think Tim's ever told me. So I assume it's the truth.

TIM FERGUSON: 'Cause I'm a man and I ignore it. It's like look at Barnaby Joyce, you know. He wakes up in the morning and goes, "No, I can't fix it, I'll shave it, but that's it, I'm stuck with it."

LIBBI GORR: The Dougs have sold out warmup shows on their way to their gigs at Melbourne Town Hall this weekend.

TIM FERGUSON: There's a point to all the humour that is, you know, dark and scary and sad. It's about loss. It's about powerlessness in the face of the biggest weapon there is, time. And that stuff, you know - that stuff's very interesting to us.

LIBBI GORR: Life's precious.

PAUL MCDERMOTT: Yeah, yeah, yeah. It becomes more precious as you get older.

PAUL "FLACCO" LIVINGSTON: It's not like we're some kind of rock band that's got together trying to kind of Spinal Tap our way into old glories. I mean, we admit that it doesn't quite work and I think that's the magic.

TIM FERGUSON: It's like playing with magic, like playing with alchemy. What if we did this to their heads?

PAUL MCDERMOTT: I think that's why suicide bombers always tend to be, you know, poor, stupid men between the ages of 15 and 22, you know. You get to a certain point and you just realise how precious and how fragile it is.

LEIGH SALES: Libbi Gorr reporting for us there.

TWITTER HANDLE: @libbi_Gorr