The cartoon journalist Tintin has been solving mysteries and bamboozling the bad guys since 1929.

There's no mystery about the enduring appeal of this cartoon character, or of the original artwork for the comic books, drawn by Belgian artist Hergé.

Fans of the boy reporter love the drawings for their simplicity of line, their energy and their humour. But the originals also attract record prices at art auctions.

We sent our own intrepid reporter, Dhananjay Kadilkar, along to the Paris branch of Christie's auction house to find out more . . .