The application relates to a modular slurry wall cutter for preparing a slurry trench that is connectable to a carrier machine, said slurry wall cutter having a frame and at least one cutting tool arranged at the frame to break up soil material. The frame here comprises an upper frame part, a middle frame part, and a lower frame part that are releasably connectable to one another, with the upper and lower frame parts being releasably connectable to one another both directly and via the middle frame part that can be arranged therebetween. The application further relates to a carrier machine, such as to a cable excavator, having a slurry wall cutter in accordance with the application.