Legal's mate is named after Kemur de Legal who won many games in the opening stage itself.
The moves are
01 e4 e4
02 Nf3 d6
03 Bc4 Bg4
04 Nc3 g6
05 Nxe5 - a sacrifice because this exposes the Queen
05 -- Bxd1 (This capture of the Q leads to mate)
06 Bxf7 Ke7
07 Nd5 checkmate