'The Office' Star -- Divorcing 'Mentalist' Hunk

The woman who played the receptionist on the British version of "The Office" is pulling the trigger on her 4-year marriage to "The Mentalist" hunk Owain Yeoman ... TMZ has learned.

Lucy Davis filed divorce papers in L.A. County Superior Court earlier this month ... citing irreconcilable differences as the reason for the split.

According to the docs, the couple separated back in January. They have no children together.

FYI -- Lucy's character was the basis for Pam Beesly on the American version of "The Office" ... which begs the question ...