What is the rarest movie poster?

While no one knows for sure which of the thousands of movie posters that have been produced is the rarest, certain ones have fetched high prices at auctions due to their rarity. Many are from classic horror films, such as 1931's Frankenstein, 1933's King Kong and 1934's The Black Cat. Other prized posters include those for 1933's Flying Down to Rio and 1927's Metropolis. A version of the latter sold for a record-setting $690,000 in 2005. On 1stDibs, explore a selection of movie posters.