Most actors can happily stand up and promote their work to the hilt because they've put time, effort and sometimes money into the movie's output.

Of course, hindsight's a brilliant thing and when a movie doesn't do what it's supposed to at a box-office, actors can then go on to reveal their true feelings on the whole thing. Here's just a snifter of some actors unleashing the beast on their own work.

9. Bob Hoskins and 'Super Mario Bros.'

Sir Bob Hoskins was one of the great English actors of our generation, starring in such classics as 'The Long Good Friday', 'Mona Lisa', 'Brazil' and 'Who Framed Roger Rabbit', not to mention countless others. However, in 1993, Hoskins decided to set his career back a few years and join the sinking ship that was the on-screen adaptation of 'Super Mario Bros.' When asked about it years later, Hoskins' musings on the topic were as follows:

What is the worst job you've done?

Super Mario Brothers.

What has been your biggest disappointment?

Super Mario Brothers.

If you could edit your past, what would you change?

I wouldn't do 'Super Mario Brothers'.

8. Malcolm McDowell and 'Caligula'

'Caligula' is often considered to be one of the worst films ever made. In a way, you have to respect what they were going for - 'Ben-Hur' meets hardcore pornography. In the most narrow sense, it achieved that aim. In a more realistic sense, however, it was absolutely awful.

Sure enough, Malcolm McDowell felt the same way. As McDowell tells it, Bob Guccione - porn kingpin and producer of 'Caligula' - basically took the footage that director Tinto Brass had shot and edited in scenes with straight-up, no-nonsense pornography. In an interview with Conan O'Brien in 1994, McDowell said that he hated the movie and called it garbage. He did remark, however, that co-star John Gielgud saw the movie THREE times.

Here's that interview.

7. Alec Baldwin and 'Rock of Ages'

Alec Baldwin's not exactly known for his tact or keeping his opinion to himself, and that's honestly refreshing in this day and age. Not surprisingly, when he was asked about the critical failure that was 'Rock of Ages', he didn't hold back.

If anything, Baldwin gave the movie both barrels. He blasted the musical as a "horrible" movie and said that he was talked into starring because he liked director Adam Shankman and Tom Cruise. "A week in you go, oh God, what have I done?" Baldwin said.

6. Mark Wahlberg and 'The Happening'

M. Night Shyamalan may have corrected his career tailspin with the likes of 'Split', but it wasn't always so. His most dire of attempts was 'The Happening' - a movie about killer trees. Yes, we're absolutely serious. As Wahlberg tells it, he signed on because he was a huge fan of Amy Adams and wanted to work with her. She, of course, ended up dropping out but Wahlberg stayed on with the thing.

Still, when asked recently about it, he's somewhat philosophical about the whole thing. "It is was it is. F*cking trees, man, the plants. F*ck it. You can't blame me for wanting to try to play a science teacher. You know? I wasn't playing a cop or a crook."

5. Matthew Goode and 'Leap Year'

If you haven't watched 'Leap Year', don't. Just don't do it. Not unless you want a horribly offensive movie that just reeks of paddywhackery. It's genuinely disgraceful on just about every level and Matthew Goode, thankfully, shares this opinion somewhat. In an interview with The Telegraph, Goode described the movie as "turgid."

"I just know that there are a lot of people who will say it is the worst film of 2010. The location was the main reason I took it - so that I could come home at the weekends... Do I feel I let myself down? No. Was it a bad job? Yes, it was. But, you know, I had a nice time and I got paid.".

4. Alec Guinness and 'Star Wars'

Although people might associate Alec Guinness with being the pinnacle of the well-mannered English gentleman type on screen, he wasn't quite so respectful when it came to talking about 'Star Wars'. In fact, most of the cast weren't fans of 'Star Wars' when they were making it, with Harrison Ford famously saying that "...just because you write these words doesn't mean you can say 'em!"

Guinness, in his autobiography, was particularly brutal about the whole thing. "I shrivel inside each time it is mentioned," Guinness remarked.

"Twenty years ago, when the film was first shown, it had a freshness, also a sense of moral good and fun. Then I began to be uneasy at the influence it might be having. The bad penny first dropped in San Francisco when a sweet-faced boy of twelve told me proudly that he had seen Star Wars over a hundred times. His elegant mother nodded with approval. Looking into the boy’s eyes, I thought I detected little star-shells of madness beginning to form and I guessed that one day they would explode."

That child probably went on to start the campaign to have 'The Last Jedi' refilmed.

3. Michelle Pfeiffer and 'Grease 2'

Very often, the first time you attempt something, you're never really going to get it right. So it was with Michelle Pfeiffer and 'Grease 2', a film so bad that some people aren't actually aware that it exists. No, really.

As Pfeiffer tells it, the whole experience was pretty underwhelming. She clashed with her co-star Maxwell Caulfield and, years later, said the film was terrible. "It was a lifetime ago really so I don’t take any responsibility. I’m SO young."

2. Burt Reynolds and 'Boogie Nights'

Most of the movies on this list, with the exception of 'Star Wars' and 'The Sound of Music', are pretty terrible and understandably disliked by their stars. 'Boogie Nights', however, is objectively a great film and can't really be argued about.

Everyone except Burt Reynolds, who was ACTUALLY IN IT.

In 2015, Reynolds was quizzed by Conan O'Brien about the movie and admitted that he was offered the role seven times - and turned it down each time. "I have a hard time with that whole… Oh, better use another adjective. I have a difficult time. It just wasn’t my kind of film," said Reynolds, and claimed he still hadn't seen it and would likely die without seeing it. Burt, man, you missed out.

1. Christopher Plummer and 'The Sound of Music'

Here's some words used by Christopher Plummer to describe 'The Sound of Music'. Sound of Mucus. S&M. Awful. Gooey. In fact, Christopher Plummer hated the movie so much that when he worked on movies afterwards, fellow actors were specifically asked not to bring up 'The Sound of Music' at all and the same went for journalists and interviewers, too.

Not only that, during the production, Plummer drank heavily and ate voraciously in order to drown out the schmaltziness of it all, with Plummer later admitting that his costume had to be refitted due to his ballooning weight. That's what Edelweiss did to Christopher Plummer.