This week’s puzzle is a chance to enter an annual national contest in which Guardian readers traditionally perform strongly and in considerable numbers. White in the diagram, playing as usual up the board, is to play and checkmate in two moves, against any black defence.
The puzzle is the first stage of the annual Winton British Solving Championship, organised by the British Chess Problem Society. This competition is open only to British residents, and entry is free. To take part, simply send White’s first move to Nigel Dennis, Boundary House, 230 Greys Road, Henley-on-Thames, Oxon RG9 1QY or by email to winton@theproblemist.