Assigned to the Eastern Fleet in the Indian Ocean in early 1942, "Formidable" covered the invasion of Diego Suarez in Vichy Madagascar in mid-1942 against the possibility of a sortie by the Japanese into the Indian Ocean. "Formidable" returned home for a brief refit before participating in Operation Torch, the invasion of French North Africa in November. She remained in the Mediterranean and covered the invasions of Sicily and mainland Italy in 1943 before beginning a lengthy refit.