 He worked in 1942 directly with Lehi founder Avraham Stern.After Stern's killing by the British, Eldad became one of a triumvirate of Lehi commanders, working together with Natan Yellin-Mor and future prime minister Yitzhak Shamir.Yellin-Mor was the diplomatic "foreign minister," Shamir the operations man, and Eldad the ideologue.