Bettiah (West Champaran): Ever heard of a lock that cannot be unlocked by anyone other than its owner? That is what sets a 78-year-old lock apart in a corner of Bihar.

Weighing about 5kg and created by one Narayan Prasad way back in 1940, the lock is now the prized possession of Narayan's son Lal Babu, a resident of Bettiah, around 200km northwest of Patna.

Lal Babu, who is in his early-sixties, boasted: "Ever since my father created this lock in 1940, nobody other than my family members could unlock it despite umpteen efforts.

"To open, it requires a sleight of hand. And it continues to be a riddle for years," he added.

The lock has a few legends associated with it.

According to one popular story running about the lock, Narayan Prasad, who created the lock, got an opportunity to display his intriguing invention at an exhibition organised by the Bettiah maharaja in 1940. A reward of 11 silver coins was announced for anyone who could open it. Bettiah maharaja Harendra Kishore wanted to buy the lock but Narayan politely turned down the offer.

Even India's premier lock manufacturers, Godrej India Limited, apparently offered Narayan Rs 1 lakh for the lock in 1972 in exchange of its patent rights. But Narayan refused.

Asked why his family members are adamant to not share the secret of the lock, pat came Lal Babu's reply: "We want to carry it as a legacy from generation to generation. Hence, we do not want to reveal it."

Born into a sculptor's family, Lal Babu is an excellent sculptor himself. His deft fingers have shaped buffalo horns into artistic creations. Like his father, he too has a passion for creating something new. This creative urge saw him inventing a new air rifle in 1971.

He got an opportunity to display his invention at an exhibition inaugurated by then Bihar chief minister Kedar Pandey. Impressed by the creation, Pandey facilitated Lal Babu's participation in the Asian Trade Fair, 1972. Pandey also assured lal babu of all possible assistance for setting up a lock and rifle factory.

But the project failed to see the light of day owing to inaccessibility to the chief minister.

Lal Babu said he was helpless because the money he had raised for setting up the factory on his own turned out to be too meagre.