Tzvi was born in 1915 in a village near Odessa, Ukraine, to Raizel and Zalman. He was educated in a socialist, anti-Zionist school (speaking Yiddish), but he decided to join Beitar and embrace Zionism. In 1933, he made aliyah, serving in the Beitar company in Ramat Gan. He joined Hagana Bet, what would soon become the IZL. In 1936, he joined the Jewish Settlement Police and was stationed in Tel Litwinsky. Even though his JSP job required him to be a Hagana member, he continued in the IZL. Sometimes he would acquire firearms from the police station for IZL training sessions with the Beitar company of Tel Litwinsky. Whenever he was on holiday, he would teach IZL courses in firearms and maneuvers. When the split occurred, he followed Yair. In order to conceal this from the IZL, he claimed that he had abandoned the underground wholesale because he could not bear the divisiveness.

As a Lehi member, Tzvi was involved in many operations. In 1943, Yitzhak Shamir (Michael) sent him to find a place near Latrun where the Lehi detainees planning their escape could find refuge. The night of the escape, he went out with Immanuel Hanegbi, with firearms for the twenty escapees, in order to get them to the safehouse. The operation was successful, and the underground was blessed by the addition of twenty new members who were experienced veterans.

Tzvi’s days as a double agent came to a close in 1946, when he participated in the Lehi attack on Kfar Syrkin Airfield and was identified by a Hagana member. He was kicked out of the Hagana, and he went underground out of concern about the British. He was transferred to Jerusalem to supervise the operations division, where he worked until the State was established. During this time, the branch undertook a number of attacks on the British. In May 1948, he joined the IDF with the other Lehi members, and he fought until the end of War of Independence in Battalion 82 of the 8th Brigade.

From 1950 until 1956, he worked in Be’er Menucha in repairing and maintaining the road to Eilat.

In 1957, he married Yocheved Mizrahi (Tamar), who was also a Lehi member, a kindergarten teacher, and they had a son and a daughter.

In 1956, he was in the settlement division of the Jewish Agency, until he retired in 1981.

He was active among the Temple Mount Faithful, and he never missed an even of the Freedom Fighters of Israel Heritage Fund, as long as he was physically able. After retirement, he volunteered at the Beit HaHayal club, until his health failed him. Tzvi was known among his Lehi comrades as a beloved, unique and passionate figure. He was friendly and sociable, always in a good mood, radiating optimism. He became a sort of symbol for the rebuilding of the Temple; in the underground he was “Old Danny,” because most of the underground members were younger than him. After the State was established, “We must liberate the Temple Mount!” earning himself the nickname “Temple Mount Danny.” After the Six-Day War, he said: “Now it shall be built!”

He passed away in the middle of Sukkot on 4.10.2001, and he was buried in Jerusalem on Har Menuhot.