The original Robby the Robot from classic sci-fi film Forbidden Planet (1956) was expected to do well at auction.
But few could have predicted this extraordinary result.
Robby the Robot is perhaps the most iconic piece of sci-fi memorabilia
The lot (which stands at seven feet tall) realised a movie prop record $5.3m, just below the $5.6m movie memorabilia auction record set for Marilyn Monroe’s white Subway dress from The Seven Year Itch in 2011.
Robby originally cost around $125,000 to build, an astronomical sum back in the 1950s. He can be manoeuvred with a remote control, or from the inside by an uncomfortably sweaty stuntman.
"This is an out-of-this-world result for one of the most loved items in movie history," explained Dr Catherine Williamson, Bonhams’ director of entertainment memorabilia.
"Robby the Robot is one of those symbols of American culture that is embedded in our DNA.
“We are thrilled for the consignor, William Malone, who has cared for Robby for so many years and we are delighted that so many of Robby's fans took the once-in-a-lifetime opportunity to see him at Bonhams.”
Horror director Malone has owned Robby from a number of years.
He said: "I'm astounded by the result, but also sad to part with him.
“However, it's time Robby finds a place where he can be displayed, and with someone who can look after him. Of course, he will leave an empty spot in my house - and in my heart."
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