The master-slave flipflop is basically two gated SR flipflops connected together in a series configuration with the slave having an inverted clock pulse.

The output from $Q$ and $\bar{Q}$ of the 'slave' flipflop are fed back to the inputs of the 'master' while the outputs of the 'master' flipflop are connected to the inputs of the 'slave' flipflop. This gives JK flipflop: