And this week the identity of the Sherlock Holmes director's new companion has been revealed as up-and-coming actress and model Mellany Gandara.
The couple were reportedly introduced by Guy's pal Robert Downey Jr, who met Mellany on the set of Iron Man. The 26-year-old beauty, who hails from Haiti, had a small part as a scantily-dressed party girl in the blockbuster.
Guy and Mellany have been pictured out together three times in the past month, most recently at Guy's pub The Punchbowl in Mayfair, Central London.
Last Monday the pair took in an Irish band at the establishment, where an onlooker said: "She looked at ease in his company". Mellany is reported to have left his house the next day.
Representatives for Guy have declined to comment on reports of a new romance.
There's also been no word on what Guy's former wife Madonna - currently dating Brazillian model Jesus Luz, 22 - makes of Guy's new relationship.