The past two years have been extremely chaotic for AC/DC, with only guitarist Angus Young and bassist Cliff Williams remaining from the five-man lineup that reigned as one of one of rock's most popular acts for the two previous decades.

With guitarist Malcolm Young forced to leave the group permanently for health reasons, drummer Phil Rudd sidelined by legal issues, singer Brian Johnson ordered off the road (at least temporarily) due to hearing loss and now Williams announcing that he too will step away from touring and recording at the end of their current Rock or Bust world tour, we asked our writers to speculate about what the future might hold for Young and company.

Will Rock or Bust be the last AC/DC album? Is this their final tour? Will Axl Rose's temporary role as Johnson's replacement turn into something more permanent, or will Johnson reclaim his position? Who's going to play bass? Will Rudd be allowed to rejoin the group? Here's what we think.

1) Do you think this will be AC/DC’s last tour? Should it be?

Matthew Wilkening: My early money was on Rock of Bust being an unannounced farewell album and tour, in tribute to Malcolm Young. But why would Cliff Williams announce that he's walking away if that was the case? He must know or think that Angus Young is going to continue on, or he'd just wait for the whole band to call it quits, right? So yeah, I think there will be more tours. As for the second part of the question: Everybody should do whatever they want, of course. It's silly to tell somebody when to retire. If you don't wanna go, don't buy a ticket.

Annie Zaleski: I don't think this will be AC/DC's last tour, but I do think it should be. Losing Malcolm Young was a big blow, and then to have Cliff Williams also plan to retire is another gigantic loss. Angus Young is absolutely the face and sound of AC/DC, but the band is greater than the sum of its parts, and while I've been impressed with Axl Rose on vocals, I think the band can only go forward for so long with just one major member left.

Nick DeRiso: I was leaning yes, after watching AC/DC lose not one, not two but three members during the course of a single album project and tour. But Cliff Williams’ public retirement announcement has me wondering if he knows something about their future plans that we don’t. As for whether they should go forward, emotion says no. But conventional wisdom says yes. There are plenty of bands of their era touring with fewer links to their original era – and some with none at all.

Michael Gallucci: As long as Angus Young is breathing, AC/DC will be around. They rebounded before, after Bon Scott's death, so there's no reason to think that they can't continue with a new singer. Just don't expect the same results that greeted Back in Black.

Jed Gottlieb: I think they’ll stop touring the day Angus Young dies. Or maybe a few days after, knowing his energy level. Our modern world allows and pushes acts to play forever. Just look at Paul McCartney, the Grateful Dead and the Monkees, who are all older than AC/DC and still on the road this summer. Should Young hang up the schoolboy knickers? No. The Rock or Bust tour was a tremendous live show, and that was because the talent and force of will of the guitarist, who is only 61. I say keep at it.

Eduardo Rivadavia: No, I think the Youngs will find a way to keep the family cottage industry in business well into future generations, by hook or by crook, even after Angus and Malcolm are both unable to perform. Before too long, they will have groomed younger, uh, Youngs, to fill their shoes and perform those classic songs onstage. Like other rock titans of their stature, AC/DC are much too large and lucrative a corporation to simply shut down, and I think we've seen enough evidence that audiences will keep on buying tickets to hear those songs -- just as long as someone, anyone, is head-banging convincingly in a schoolboy outfit. I used to think that only Kiss would transition smoothly into postmortem touring with the help of human stand-ins, robots or holograms, but I'm increasingly convinced that any successful rock band can keep their show on the road forever more, given proper planning.

Michael Christopher: Personally, I think they should end on a high note. Rock or Bust was their best reviewed album in a long time, and they dodged a bullet in being able to successfully make up the dates without Johnson by having Rose come in. But with Williams retiring, they don’t want to be that band who tours with only one original member – even if Angus Young is that member. All that said, I think the shows with Rose were so well-received that it will prove to be too lucrative not to continue.

2) Will Rock or Bust prove to be their final album? If not, who’s going to sing on the next one? Brian Johnson? Axl Rose? Somebody else?

Wilkening: These first two questions are rather interconnected, so to quickly reiterate: Yes, I think there will be at least another AC/DC album. During that recent hour-long Q&A session in London, Rose mentioned that he and Young have been informally throwing song ideas at each other. Brian Johnson rules forever, but if he's medically banned from participating, It's hard to deny an incredible amount of curiosity about what Rose and Young could do together. So, second to a Johnson recovery, I'm going to root for Axl/DC.

Zaleski: I don't think this will be their final album. However, I do think Brian Johnson will return to the group, at least in the studio, since it seems like live performing was more of a concern with his hearing loss.

DeRiso: I’m intrigued by how well Axl Rose has meshed with the group onstage. There have also been indications that they are writing together while completing these final dates. I think it’s worth exploring.

Gallucci: Albums are coming few and far between these days, but I think they still have a couple left in them. If Angus Young wants to keep the band going, he will at this point (just look at the recent Axl Rose addition on tour for proof). Will Brian Johnson be back for another album? Maybe. If not, look for Young to replace him with a relative unknown -- just like he did when Johnson stepped in for the late Bon Scott.

Gottlieb: I’m sure Angus Young has the riffs in him. But the problem is lyrics, which I admit is a silly thing to say for a band with such silly lyrics. I say Young writes 10 pieces of music and gives them to 10 singers to finish. Why not start with Axl Rose, Steven Tyler, Rob Halford, Bruce Dickinson, James Hetfield, Alice Cooper, Joan Jett, Billy Idol, Dave Grohl and Ozzy Osbourne? Whoever does the best job gets to front the band. I hope Jett wins.

Rivadavia: Barring a sudden serious health issue, I have a feeling that Young will muster enough troops for another AC/DC album. Stevie Young will be ready and willing, as will Chris Slade, and I could even see Angus Young convincing Cliff Williams to un-retire long enough to play on the record. Ditto Brian Johnson, who may be healthy enough by then, and would be a wise political choice on Young's part, to help overcome any lingering public misgivings about the AC/DC "brand" after the controversial (but obviously relatively successful) Axl Rose hire.

Christopher: If Brian Johnson comes back, by all means, make another record. But if he can’t do it, for whatever reason, Axl Rose would be the obvious choice, especially as he’s shown interest in working with Angus Young. With the departure of Cliff Williams, though, why not create a new project and not have to worry about tainting the AC/DC name? Remember, this is one of the few bands that was not only able to replace its singer, but also to go on to have more success. I’m not saying Axl Rose is another Gary Cherone, but why take the risk?

3) If the band continues on without Cliff Williams, any guesses as to who plays bass?

Wilkening: Well, Angus Young doesn't have a son, so that's out ...

Zaleski: Perhaps Airbourne bassist Justin Street. The band has toured with (and is influenced by) AC/DC, and he'd no doubt do his best to honor Williams' legacy. George Young could also be an option, but I'm not sure if he'd be up for the rigors of a massive tour.

DeRiso: Bringing back Rob Bailey or – maybe better still – Mark Evans would probably do much to mollify those who think AC/DC are becoming too disconnected from their roots.

Gallucci: Does it matter? AC/DC have always been about Angus Young and the singer. Everything else in the band is interchangeable. Nothing the band plays is too demanding, and aside from the guitar and voice, nothing is too defining either. Anyone with basic hard-rock skills can step into the position.

Gottlieb: Williams can hold down the low end like a champ, but he’s not irreplaceable. The obvious pick would Duff McKagan, and it would help ticket sales if both he and Axl Rose were in the band -- not that AC/DC need help with sales. But Tommy Stinson or Nikki Sixx would do great too.

Rivadavia: It sure as hell won't be Mark Evans, not that he has any delusions that this will be the case. So my best guess is that yet another Young family member will be drilled to keep those pumping bass lines clicking like a metronome. Because of the recent Axl Rose liaison, one inevitably considers the possibility of Duff McKagan, but that opens such a trans-dimensional box of worms resulting in a full-on AC/DC-GNR corporate merger that my brain can't quite process it at this time.

Christopher: Stephen Harris – who some might remember as Kid Chaos or Haggis – would be an excellent choice for bass. The music AC/DC plays doesn’t need a Billy Sheehan type, but rather someone who can lay a solid foundation down along with the drummer for the Angus Young riffs to stand on. Harris played with the Cult during their Electric tour, and later went on to form the Four Horsemen, an underrated act heavily influenced by AC/DC. As a bonus, if Axl Rose does continue with the band, Harris would be a familiar face: He filled in for Duff McKagan with Guns N’ Roses for one show while they were opening for Iron Maiden in 1988.

4) Will Phil Rudd ever return to AC/DC? Should he?

Wilkening: None of our business to say "should" or "should not." If he's no danger to himself or others, and the band wants to give him another chance, great. He's the most natural fit for them musically. Besides, I need Chris Slade freed up for a reunion album and tour by the Firm.

Zaleski: I don't think so, and I don't think he should. I think he's too much of a liability, due to the instability surrounding his personal life. AC/DC have had so much lineup chaos in recent years, they don't need to court any more.

DeRiso: No and no. Chris Slade has always been a sturdy figure for AC/DC, on- and offstage.

Gallucci: Same answer as the Cliff Williams question: does not matter. Anyone can step in here. No reason to go back to the guy they kicked out.

Gottlieb: No and no. I have no beef with Rudd, but a hundred drummers can do his job. Chris Slade has been doing it off and on for years with missing a beat.

Rivadavia: I don't think so. Even though Rudd will always be the inimitable heartbeat of AC/DC, the others did manage without him for 20 years, and his recent legal issues are too big a distraction to make a rekindling of the partnership worthwhile. I don't see much of upside for Rudd either, beyond the "can never make too much money" argument. Personally, I think that his life as the "Hugh Hefner of New Zealand" sounds much more intriguing than yet another tour of duty with AC/DC. I'd watch that reality show.

Christopher: If Phil Rudd can keep his act together, then why shouldn’t he be given another chance? On the other hand, Chris Slade deserves major kudos for having stepped in on such short notice and delivering the goods like he has. It lent an air of familiarity to the shows, which were already missing the presence of Malcolm Young on the Rock or Bust tour. But Rudd coming back would make the departure of Williams a bit easier to take, certainly for the fans. And while Slade has the excellent The Razors Edge in his back pocket, Rudd has almost everything else.

5) The band reportedly filmed its Wrigley Field shows (with Brian Johnson on vocals) for future home video release. Think there will also be an Axl Rose-fronted concert released?

Wilkening: I'd line up to buy both versions of this. But if they asked me, out of respect to Johnson, maybe what they should do is put his version out first and let it have all the attention to itself for awhile.

Zaleski: If they were smart, yes, as Guns n' Roses fans would probably buy it in a heartbeat. But I'd think that would depend on whether GNR have any sort of recording or video plans of their own, as I'd think that Axl Rose wouldn't want to undercut his own band's releases.

DeRiso: Wouldn’t that be cool? Package them together for a deluxe edition. Bonus material includes hours of die-hard fans arguing over who was better.

Gallucci: Doubtful -- too may legal hoops to jump through to get the Axl Rose-fronted shows out there. Even if he wanted to, somebody at a record company or in management will make this more trouble than it's worth.

Gottlieb: Probably, because money talks and AC/DC knows that so well. They probably make more off sales of those light up devil horns than they do from albums these days. The fact is these guys know how to move product. If they can sell 10,000 Rose-fronted concert Blu-rays, then they will. Will I ever watch? Hell, no, but I’ll see them live with Rose or almost anyone.

Rivadavia: Absolutely, there's too much money on the table (and, likely, contracts were already signed, sealed and delivered months ago) for there not to be a video release of the Wrigley concerts with Brian Johnson. And I have to think a separate video release of an Axl Rose show is inevitable too, unless Guns N' Roses are still flying high with their reunion -- the timing isn't right for the brands. It's bound to get released in due time, though, and it'll be called Whole Lotta Axl.

Christopher: I’d love to see a Rose-fronted home-video release. Those European shows and upcoming Stateside ones are a moment in time that you want to preserve. Plus, it would be great for fans that weren’t there in person to see AC/DC breaking out gems like “Touch Too Much,” “Riff Raff” and “Given the Dog a Bone.” Then again, Rose has never been very liberal in putting out live videos with Guns N’ Roses, having done just two in their almost 30-year career.

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