He is also known as first love of Joseph Stalin's daughter, Svetlana Alliluyeva. According to Stalin's daughter, that was the reason for Kapler to be sentenced in 1943 to five years in a labour camp on charges of anti-Soviet agitation. He was sent to Vorkuta region. In 1948, he was convicted second time and spent five more years in Inta labour camps, being finally released only in July 1953. After returning from Gulag he continued working on cinema and TV. His last wife was poet Yulia Drunina.