10. Val Kilmer - Batman Forever
From the mid-1980s through to the mid-1990s, Val Kilmer was one of Hollywood's hottest young properties.
With successful roles in the likes of Top Secret!, Real Genius, Top Gun, Willow, The Doors, Thunderheart, and Tombstone, it seemed like Kilmer was set to be a popular Hollywood mainstay forever more.
Kilmer being cast as the Dark Knight in 1995's Batman Forever seemingly cemented his standing in the industry, and the film's solid commercial performance suggested he'd return for at least a few sequels.
But in actual fact, Kilmer opted not to reprise the role for Batman & Robin, and after appearing in Michael Mann's heat later in 1995, found himself suffering through a brutal run of critical and commercial duds.
In honesty his career never recovered from turning down Batman, with his last 25 years in the business being largely defined by the tawdry likes of The Island of Dr. Moreau, The Saint, Red Planet, Alexander, and in more recent years The Snowman and a slew of straight-to-VOD action duds.
Though Kilmer has certainly appeared in a few great movies since Batman & Robin - namely Kiss Kiss, Bang Bang and Bad Lieutenant: Port of Call New Orleans - he's never regained that leading man box office appeal, which combined with his reputation for being difficult to work with hasn't served him well.
Kilmer will appear in cameo form, however, in the upcoming Top Gun: Maverick, yet due to a recent bout with throat cancer reducing his voice to a rasp, it's sadly unlikely he'll ever regain his A-lister status.