An automated in situ heat induced antigen recovery and staining method and apparatus for treating a plurality of microscope slides. The process of heat induced antigen recovery and the process of staining the biological sample on the microscope slide are conducted in the same apparatus, wherein the microscope slides do not need to be physically removed from one apparatus to another. Each treatment step occurs within the same reaction compartment. The reaction conditions of each reaction compartment for treating a slide can preferably be controlled independently, including the individualized application of reagents to each slide and the individualized treatment of each slide.