Der Unüberwindliche (1928)

The Italian acrobat Silvio Spaventa is the sensation of the circus where, every evening, he performs a death-defying act with his partner, Rina Pera. One evening, the respected jeweler Mr. van Teelen and Police Commissioner Hellberg attend a performance. Watching Spaventa’s feats, the two men make a strange bet: they wager that Silvio can not only open the locks on the chains that bind him in front of everyone, but also any safe whatsoever. They suggest that Spaventa try his luck with the safe in van Teelen’s home. It has double armor plating and is considered impenetrable. Silvio accepts the bet and succeeds in his attempt to crack the safe. But van Teelen’s unscrupulous lover, Heloise, also learns about it and informs a gang of crooks of the experiment. A diamond smuggler would very much like to get his hands on van Teelen’s jewels, and since he is in contact with the criminals, he hires the thieves to steal the diamonds. While van Teelen is away from home, Spaventa is once again invited to his house, supposedly by van Teelen, to repeat the experiment. This time, however, the criminals are waiting for him there and force Spaventa to crack the safe again. When van Teelen unexpectedly returns, he believes Silvio is trying to rob him. But Silvio is able to use all his acrobatic skills and tricks, prove his innocence, and bring the real culprits to justice.