Brillouin-enhanced four-wave mixing (BEFWM) in CS2 has been investigated experimentally using an iodine laser. The output signal from BEFWM recovers the original laser frequency by frequency-upshifting a Stokes-shifted probe beam, suitable for subsequent amplification in a chain of iodine laser amplifiers. The power conversion efficiency of 30% through BEFWM and the pulse compression from 50 ns to 3 ns between the incident laser and the output signal have been obtained.