Only 121 Ferrari 365 GTS/4 Daytona Spiders (not including the coupe) were built and this is one of them. Thing is, it hasn't been seen in public for 20 years. Set to hit the auction block at RM Auction's Monterey event next month, this 1972 Ferrari Daytona Spider is nicknamed "The Hidden Spider" due to its two-decade disappearance. So what happened, exactly? After making an appearance at the Rodeo Drive Concours d'Elegance in 1997, the owner stored it in his family garage and locked the door.

This family has actually owned it since 1983 after it passed through a series of owners after its US arrival from Italy in 1972. When this family took possession in '83, the Daytona had less than 35,000 miles on the clock. Today there's just 36,513 miles. Reportedly, it's never been restored or taken apart, but the body was refurbished in its original Rossa Chiaro paint and the interior reupholstered in tan leather back in 1977. It's amazing how good that work still looks today. Those Borrani wire wheels are as stunning as ever. Under the hood, the V12 is also all original, but the car does come with a reproduction tool set and a correct set of Daytona books, such as a spare parts catalogue and service handbook.

More recently, some basic mechanical work was done, like flushing the fuel system, rebuilding the carburetors, and some repairs to the electric system (it's Italian, remember). Some lower body paintwork was also touched up. RM Auctions hasn't listed a price range, but similar past examples have gone for almost $1 million. Photos courtesy of RM Auctions.