Query: In 1947, what company did Universal buy a stake in?
Context: Universal-International became responsible for the American distribution of Rank's British productions, including such classics as David Lean's Great Expectations (1946) and Laurence Olivier's Hamlet (1948). Broadening its scope further, Universal-International branched out into the lucrative non-theatrical field, buying a majority stake in home-movie dealer Castle Films in 1947, and taking the company over entirely in 1951. For three decades, Castle would offer "highlights" reels from the Universal film library to home-movie enthusiasts and collectors.