At MST3K's Facebook page, it had a trivia question that's appropriate since the Oscars are coming up Sunday: what's the only movie shown on MST3K that won an Oscar? The answer is Space Travelers, which was a re-edited version of Marooned. It won for special effects, but it wasn't safe from the riffing.
A blog called Peanut Butter and Awesome written by someone called Jeremy listed three movies the writer will watch instead of the Oscars: Psycho II, Night of the Lepus and McBain. Those three movies, readily available on VOD at Rifftrax all have actors who were up for Academy Awards. Psycho II had Anthony Perkins, Meg Tilly and Robert Loggia, Night of the Lepus has Stuart Whitman and Janet Leigh. McBain starred Christopher Walken, who won for The Deer Hunter.
That leads to looking at the Rifftrax and MST3K libraries to see which movies had real actors in really bad movies.I'm not counting the mp3 riffs because they take on real movies. This is mainly from the VOD library.
Hawk the Slayer features a hero who must end the tyranny imposed by his brother Voltan, played by Jack Palance, who won for City Slickers, Despite a fine career in TV and film, he's done some cheesy roles like an evil warlord. He is also seen in Angel's Revenge as a drug pusher and Outlaw of Gor as a high priest helping some sexy evil woman to take over a kingdom. That's also the movie were the word "Cabot" is said eleventy hundred times.
This was back in the days where people thought today's video games are tomorrow's movie blockbusters. While Resident Evil was a good example of that idea. this wasn't. Bob Hoskins, who plays Mario, has long said he shouldn't have taken this job. His role in Mona Lisa earned him an Oscar nomination in 1986. The big bad in this movie, King Koopa, is played by Dennis Hopper, who was nominated for writing and acting in his career. So, this is a selection that has the best pedigree.
This movie, about a cyborg from behind the Iron Curtain who wants to defect, features Christopher Plummer as a business magnate who wants to set up a new world order, as magnates do. It also features a short appearance by Martin Landau, three years before Ed Wood.
This is a classic example of "what the heck is he doing here?" John Huston won two Oscars for directing, and can claim to be someone who directed his father and daughter to Oscars, too. So how come he was part of this movie about a squabbling family whose boat is lost in an area where ships disappear without a trace? It might have been to fund the movie, Wise Blood. He's done other unlikely roles in his career, too.
Other Rifftrax selections that included Oscar winners or nominees include Nightmare at Noon (George Kennedy), The Boy in the Plastic Bubble (John Travolta) and Little Shop of Horrors (Jack Nicholson in a very early role).
On the MST3K side, there are some Oscar winners and nominees. Remember Robot Monster? The score was written by Elmer Bernstein, who went on to work on classics like The Magnificent Seven, Airplane and Ghostbusters. He won an Oscar for Thoroughly Modern Millie, a goofy musical back in 1967. Gunslinger may have had Beverly Garland, but it also had John Ireland, who was nominated for All The King's Men. City Limits, all about a teen apocalypse, had James Earl Jones, who was nominated for The Great White Hope. Kitten With a Whip featured Ann Margaret as a crazy teenager exploiting a really dumb senatorial candidate played by John Forsythe. She would be nominated for Tommy and Carnal Knowledge. Revenge of the Creature, which started the show's tenure on Syfy, included Clint Eastwood, who also won twice for directing. Merlin's Shop of Mystical Wonders had Ernest Borgnine, who won for Marty. Hamlet, the German TV version, had Maximillian Schell in the title role. He won for Judgement in Nuremberg.
This only proves in the case of out favorite actors, writers and directors, they had to start somewhere, or continue their careers as best they could. The best can exist in less-than-ideal conditions.