Which mathematician proved Fermat's Last Theorem in 1994?

Andrew Wiles, who worked on it in near-total secrecy for seven years - almost unheard of in modern mathematics, where the norm is to publish and collaborate. He told almost nobody, published unrelated results occasionally to avoid suspicion, and worked in his attic.

Fermat had written in the margin of a book in 1637 that he had a marvellous proof which the margin was too narrow to contain, and the claim went unproved for 358 years while defeating essentially everyone. Wiles had read about it at ten in a library book and decided then that he would solve it, which is the kind of thing that is only charming if it works.

It then fell apart in public. He announced the proof in 1993, and during peer review a serious gap appeared in one section. He spent over a year trying to close it, was on the point of giving up, and found the fix in September 1994 - by combining the failed approach with an earlier one he had abandoned. The published proof runs to over a hundred pages, relies on machinery invented long after Fermat, and essentially nobody believes Fermat had it.