Mark Tinta got me thinking about this on the horror board where everyone was discussing just what in the hell Henry Fonda was doing in TENTACLES. Research for ON GOLDEN POND, perhaps? A Tinta quote:

So what is the all-time worst case of an A-lister who has gone down the tubes? Richard Harris in STRIKE COMMANDO 2 is a great example. Here is a guy who is a multi-nominated leading man and respected stage actor working with a director who gave us HELL OF THE LIVING DEAD (1980) and VIOLENCE IN A WOMEN'S PRISON (1982).

Has anyone sunk lower than that? Oliver Reed perhaps? I guess I should narrow it down to former A-list leads because, honestly, we could talk Madsen and Sizemore all day (although I don't think any of them could top veteran sidekick Donald Pleasance popping up in FATAL FRAMES). And no cameos. I'm talking full on lead roles.

PS: And, no, Stephen Geoffreys doesn't count!

Were these people A-list in the sense that Julia Roberts and George Clooney are A-list? Not always, but they were respected, often award-nominated actors who definitely hit a rough patch.

Treat Williams was a promising young actor in classic films by Sidney Lumet and Sergio Leone, and just a few years later, was in Tonino Ricci's NIGHT OF THE SHARKS (1987, released in the US in 1990).

After WALL STREET, DA, and JUDGMENT IN BERLIN, Martin Sheen was in a whole slew of bad, mostly straight-to-DVD movies from 1989 to around the premiere of THE WEST WING. I mean, BEVERLY HILLS BRATS? TOUCH AND DIE? GUNS OF HONOR? DILLINGER AND CAPONE for New Horizons, with F. Murray Abraham?

Harvey Keitel and Klaus Kinski in the wretched Spanish sci-fi atrocity STAR KNIGHT (1986). Maybe doesn't count for Kinski, since he made no secret of going where the money is, even turning down RAIDERS OF THE LOST ARK because VENOM paid more.

Telly Savalas, in one of his last roles, in Fred Olen Ray's mid-1990s Skinemax fixture MIND TWISTER (1994).

Arthur Kennedy in EMANUELLE ON TABOO ISLAND (1977).

Richard Conte's final role came in the vulgar Italian EXORCIST ripoff NAKED EXORCISM aka THE POSSESSOR (1977)

I was almost tempted to mention John Carradine and his Olen Ray expeditions, but by the time his career was winding down he had done tons of those kinda flicks.

Yeah, but most of Carradine's appearances in these things Fred Olen Ray and/or Jim Wynorski outings were cameos (or, in the case of JACK-O, unused footage appearing in a film seven years after his death). Savalas had the lead role in MIND TWISTER, playing a detective investigating a murder in between gratuitous scenes of ROAD HOUSE's Gary Hudson getting it on with Suzanne Slater and Erika Nann (and, presumably, giving the viewer a chance to re-energize). I'm sure Savalas shot it in a couple of days, but from what I recall, he's in the whole movie.

This one just popped into my head:

Rossano Brazzi going from SOUTH PACIFIC to co-starring with "Boris Lugosi" in the Dick Randall-produced FRANKENSTEIN'S CASTLE OF FREAKS.

And these weren't leading roles, but more extended cameos, but how can we forget Mel Ferrer, going from RANCHO NOTORIOUS, LILI, WAR AND PEACE, and the cover of Life with ex-wife Audrey Hepburn, to Umberto Lenzi's EATEN ALIVE and NIGHTMARE CITY?

Oh! And Glenn Ford turning up in 1991's RAW NERVE, with Traci Lords, Jan-Michael Vincent, Ted Prior, Sandahl Bergman, and Randall "Tex" Cobb!

Orson Welles?

Joan Crawford in TROG is the classic one, right?

My vote goes to Veronica Lake in FLESH FEAST. Has anyone else who was once a star been in anything worse than that flick?

Roy Scheider appeared in a really slipshod horror flick in the early 90s, THE DOORWAY, which seemed quite a bit worse than even the other DTV stuff he did a lot.

Burt Reynolds has been in some embarassments in recent years, CRAZY SIX (also with Rob Lowe) being one of the worst and most incoherent....

I don't think I've ever seen WELCOME TO ARROW BEACH but it doesn't sound like the highlight of Laurence Harvey's career. Same goes for Basil Rathbone in HILLBILLYS IN A HAUNTED HOUSE. Well, why don't I throw a third one in here: CUBAN REBEL GIRLS with Errol Flynn (and his 16 year old girlfriend). Note to myself: get a copy of this one. I've got more books about Flynn than any other actor.

All great suggestions!

Gah, I can't believe I didn't think of Bela Lugosi and his foray into Ed Wood's world. Bela was no Richard Harris, but he was quite a big star back in the day.

I'd put Aldo Ray (SWEET SAVAGE) and Cameron Mitchell (DIXIE RAY, HOLLYWOOD STAR) appearing in hardcore porn movies near the top of this list.

I think those might be the best examples. I ruled Stephen Geoffreys out because he made a choice to participate in porn. But to be in a porn film only to act? That is, pardon the pun, hardcore.

Well, it's not Ray's or Mitchell's non-active participation in hardcore porn, but more along the lines of Fonda in TENTACLES: Van Johnson landing on the Italian D-list in the the late '80s/early '90s with TAXI KILLER, KILLER CROCODILE, and DELTA FORCE COMMANDO 2.

Boris Karloff didn't fare all that much better with dreck like Fear Chamber.

My thoughts run to...
Myrna Loy and Gloria Swanson in AIRPORT '75
Henry Fonda, Fred MacMurray, Olivia de Havilland and Richard Widmark in THE SWARM
Jack Lemmon, James Stewart, Joseph Cotten and Olivia de Havilland in AIRPORT '77

And let's not forget the lead, Michael Caine!

Not the highlight, but not an embarrassment either. He directed this movie, and in the press defended it to the end -- literally, since he was overseeing the editing from his deathbed.

Val Kilmer is entering this sad fraternity. Oscar winner Cuba Gooding, Jr. has been there for a while. Anyone who had an A-list career that suddenly dives into DTV is treading heavy water. But perhaps like Martin Landau in his D-list years (THE BEING, etc.) they can swim against the tide, as I extend this metaphor...

Wait, is THE SWARM worse than JAWS THE REVENGE?

And both are in HARDWIRED, out on DVD Tuesday!

The examples given so far are mainly 'how the mighty have fallen' exploitation fare and (former) star-studded disaster pix.

I like these sorts of films as a rule and can't judge them worsts on principle (though TROG is truly awful, I admit).

The films with big stars that truly scare me are the vanity projects aging stars with clout foolishly encourage. Elizabeth Taylor has made many very awful choices of this kind in her later career. ASH WEDENESDAY is particularly dreadful in this regard and it doesn't do Henry Fonda any favors either. I prefer his euro-exploitation roles. Luckily for him he still had enough clout and taste to get the Sergio Leone treatment versus the Sergio Bergonzelli.

Christopher Walken's career seems to defy the whole notion of the 'fallen star' syndrome. In the run up to his Oscar nom for CATCH ME IF YOU CAN, he did POOLHALL JUNKIES, ENGINE TROUBLE and PLOTS WITH A VIEW (all indie/DTV productions) as well as THE COUNTRY BEARS for Disney. And his whole career is marked by this kind of work pattern.
By adopting this approach to work, he has managed to retain a level of both respect and ubiquity. And let's face it, when you're making PUSS IN BOOTS for Cannon at the tail end of the 80s, you have to retain a sense of humour (and absurdity) to call it your favourite role.

That may top it because, if I recall, he couldn't collect his Academy Award for HANNAH AND HER SISTERS because he was in Jamaica filming JAWS THE REVENGE!

Malcolm McDowell, Peter O'Toole, John Gielgud, and Helen Mirren were probably quite surprised to see the final version of CALIGULA.

During the depths of his cocaine addiction, Tony Curtis was reduced to appearing in Ulli Lommel's BRAINWAVES and OTHELLO, THE BLACK COMMANDO (a movie I would happily watch if I could ever find a copy!).

Western fans might nominate Lash LaRue, who appeared in HARD ON THE TRAIL, aka HARD TRAIL. One of those versions was a softcore flick with people like Monica Gayle. I don't imagine that Lash knew that the film would be released as a softcore oater!

Very true although I'd argue that all four of them give lively performances in that film. Would you rather watch McDowell in CALIGULA or Rob Zombie's HALLOWEEN II (a movie which I kind of liked despite the fact that McDowell seems to be sleep walking through his role and edited in after the fact) or any of the other many, many mundane and anonymous straight-to-video paychecks he's collected?

In all honesty, CALIGULA probably IS the worst movie that any of those people have appeared in, but at least in the case of Malcolm McDowell, I suspect that it is not his least watchable.

Ava Gardner in THE SENTINEL?

Worse than EARTHQUAKE? Sleazier, definitely.

I'd hesitate to include CALIGULA because, while a smut flick, it's an ambitious smut flick. And the 1977 THE SENTINEL was a big-budget Hollywood movie with a ton of old-timers in it, not just Ava Gardner. We should approach this from the example Will made, which, to me, is the most bewildering bit of casting I've ever seen: Richard Harris in STRIKE COMMANDO 2. A sequel to a film so bad that even Reb Brown didn't return from the original. Yes, THE SENTINEL is trash, but what the hell is Harris doing in a Bruno Mattei film? And he's in the whole thing! It's not just a cameo!

Whoever mentioned Veronica Lake in FLESH FEAST--another great example. Aldo Ray, Cameron Mitchell and Lash Larue--intentionally or not--appearing in hardcore porn. THAT'S a great example. A bad big-budget movie is just a bad, big-budget movie. They happen every week. Something comparable would be, just off the top of my head and totally hypothetical: if Morgan Freeman had been in MEGA SHARK VS. GIANT OCTOPUS. Or if, today, Tommy Lee Jones turned up as the bad guy in a Romania-shot, straight-to-DVD Seagal outing. Something so WTF? that it defies comprehension and demands an explanation. Like Henry Fonda in TENTACLES.

Here's a good one that no one's mentioned on this thread, but it came up when someone reviewed it: just a few years after an Oscar nomination for CHAPLIN, Robert Downey Jr was fourth-billed in DANGER ZONE, a South Africa-shot DTV action flick from NuImage. WTF?!

I wouldn't even say Michael Caine in JAWS: THE REVENGE. Big-studio movie--it's obvious why he did it: $$$. Now, if Michael Caine had appeared in Castellari's GREAT WHITE or Mattei's CRUEL JAWS...

Let's hop in the Wayback Machine, Sherman, for a classic Hollywood comedown.

Mae West in "Sextette." Here was the woman who almost single-handedly saved Paramount as one of the most popular actresses of the 1930s. And she ended her career with this blood-chilling vanity project. It's not so much that she's bad in it, but that it looks like a rehearsal for her final appearance in the slumber room.

And she took a few colleagues along with her on this humiliating misadventure: Tony Curtis, Dom DeLuise, Timothy Dalton, Ringo Starr, George Raft, George Hamilton, Walter Pidgeon, and Regis Philbin (!!).

The only remaining question is whether it was better for West to end her screen career with this bow-wow, or with her previous film (eight years earlier), Myra Breckinridge, one of the greatest star-studded train wrecks in film history. (Though without "Myra" we never would have known that Raquel Welch really knows her way around a strap-on.)

George Raft was the star of Mae West's first film, NIGHT AFTER NIGHT (1932) and he made a cameo in her very last, SEXTETTE (1978). Raft had one more film in him after that, THE MAN WITH BOGART'S FACE (1980). West and Raft died two days apart in November 1980.

But if SEXTETTE never existed, you'd never have this to enjoy. Only Timothy Dalton, an actor with a truly eccentric resume, could have appeared in this.

Paul and George presiding over the corpse that was the SGT. PEPPER movie (1978) in the final album cover-like frieze, with a wacky cast of 70's-era "stars," is pretty low...even Ringo passed on that opportunity.

Buster Keaton sure slid through a lot of bad stuff after his career went down the tubes at MGM. The few early 30s talkies I've seen are admittedly no better or worse than any other B effort of the time but he went on to some really obscure stuff and then beach films in the early 60s.

Did anybody mention Lugosi in the Ed Wood films?

Never seen any of Rita Hayworth's final films but have always heard they're torture (The Bastard, The Naked Zoo).

Mickey Rooney appeared in some dubious works, most (un)notably The Manipulator/BJ Lang Presents.

And SILENT NIGHT DEADLY NIGHT 5: THE TOY MAKER!

I would be pretty stunned if Rooney ever made a film worse than William Grefe's THE GODMOTHERS.

Looks like we may have to add a Rooney Wing to the Disgraced Stars Hall of Fame. I'd never heard of The Godmothers but Steve Puchalski's review has me dying to see it.