Background: "Animal-type melanoma," "pigmented epithelioid melanocytoma," and "epithelioid blue nevus" are melanocytic proliferations typified by intense pigmentation. Diagnosis of such lesions may be challenging because of lack of criteria on one hand and because of conceptual difficulties on the other. Objectives: Critical explanation or interpretation of texts about animal-type melanoma and entities related to it. Patients/Methods: Review of the literature in two parts and presentation of own examples of markedly pigmented melanocytic lesions in a third part of a series of articles. Results: In this first part, the origin of the idea of "animal-type melanoma" is presented and followed to the point where a new "paradigm" is introduced in which benign and malignant lesions become "indistinguishable." Conclusions: Our review demonstrates that the subject of animal-type melanoma is simply incomprehensible. The second part of this review will address the literature pertaining to "pigmented epithelioid melanocytoma" and "epithelioid blue nevus," followed by a third part presenting various cases of "deeply pigmented" melanocytic lesions together with criteria to assess these very challenging lesions.