Simcha was born in 1908 in Romania to Shmuel Mordechai and Beila Sheina, a Zionist and traditional family. At age sixteen, he made aliyah and joined his brother Yitzhak, who already lived in Jaffa and sold lumber for construction. Simcha worked with his brother. Many members of his family moved from Europe to the United States; Colonel David Marcus was his cousin.

In 1943, Simcha married Zelda Morgenstern-Hashahar. He soon became a corporal in the British Police, and he was stationed on guard duty at the entrance to Sarona (now the Kirya). This is where the important Mandatory offices were located, and senior officers, detectives and clerks lived in it.

This job made him very valuable to Lehi, and he was contacted in 1943. He was able to give them a detailed blueprint of Sarona, including access points, staff offices, numbers of vehicles and many other specifics.

This allowed Simcha to help Lehi significantly. He had many talents as well, including building and painting. The Shpilner home became a meeting-place and hideout for senior Lehi members, as Natan Yellin-Mor wrote of in his Freedom Fighters of Israel. Simcha constructed hideouts for wanted Lehi men, one of which was built on the property of Ida and Yitzhak Gazit.

Simcha even built one himself, behind his bookcases. In 1946, Simcha left the police to become a contractor. He worked independently, mainly doing small projects. However, he was not very successful in this occupation, and he had some difficulties.

The Shpilners had three children.

Simcha loved his people and his land, and he was ready to sacrifice everything for them. His many paintings decorate the home of his widow and children.

He passed away in 1976.