MKV is a highly popular container format. Users prefer MKV because it holds high-quality video (often 1080p or 4K), multiple audio tracks (e.g., 5.1 surround sound), and subtitles in one file. For Planet Earth, an MKV file is ideal because the cinematography demands high bitrates.
The BBC streams Planet Earth (both 2006 and 2016’s Planet Earth II) in HD. While you cannot download an MKV, the iPlayer app allows offline downloads for 30 days. vegamoviesnl planet earth s01e01mkv verified
Even if you find a file, it may be:
The BBC’s original Planet Earth has been remastered in 4K HDR. Pirated copies rarely match this standard. MKV is a highly popular container format