Hugh Bonneville, Allen Leech mark end of an era at 'Downton'

"Downton Abbey" a new era for Irish actor Allen Leech

WATCH: Downton Abbey stars: Where are they now?

Tom Branson starts off at #DowntonAbbey as a chauffeur, but eventually becomes a member of the Crawley family when he marries Lady Sybil. After Sybil’s passing, Tom is left to bring up their daughter alone. He goes on to become a co-agent for the estate with his sister-in-law, Lady Mary, but is reluctant to adopt the upstairs style due to his proud Irish roots. However, once Tom opens his heart to Queen Mary’s lady-in-waiting and cousin of the Crawleys, Lucy Smith, he has fully adjusted. They ma