The Novotny (also often spelled as Nowotny, even in non-German sources) is a device found in chess problems named after a problem from 1854 by Antonín Novotný, though the first example was composed by Henry Turton in 1851.
The key (first move of the solution; see Glossary of chess problems) is 1.Nb2 (see algebraic notation).
Problemists would generally agree that a single Novotny with no other play, as in this example, makes for a relatively uninteresting problem.
It is by R. C. O. Matthews, was published in the British Chess Magazine in 1957 and won the Brian Harley Award.
In the other two lines, that rook is captured, meaning it cannot execute the Novotny, but also meaning the square vacation is no longer necessary (the white knight can simply capture the black piece on b5).
The key is 1.Qd6, which is a Novotny interference with the black rook and bishop on b8, so threatening 2.Ne5# and 2.Nxd2#.
Just as these Novotny lines work as a pair, so the other black defences work in pairs: The Novotny theme occurs extremely rarely in actual play.
The strong English master Amos Burn produced such an example in an offhand game in 1910 (see diagram).
[1][2] In a seemingly desperate position, with his king apparently about to fall to a powerful attack by White's pieces, Burn played 33...Qg4!!
Burn won in 15 more moves and was to comment afterwards that his 33...Qg4 demonstrated that there is an element of luck in chess.
[5] The Novotny theme was played in David Navara vs Anna Dergatschova-Daus, Ordix Open (2007), Mainz, 2007.