Fretwell and Milbourne began work at the agency this month, and come from Miles Calcraft Briginshaw Duffy, where they have worked since October 2000.
Mahoney said: "We really need a right-hand team for Andy and me, as we want to spend more time nurturing the talent we have now in the department. Their experience both on big brands and pitching for new business will be invaluable."
Fretwell added: "We like the agency and have admired Mick and Andy's work - they have an infectious enthusiasm and energy which is hard to resist. And, coming from MCBD, we know we like the buzz and atmosphere of a smaller agency."
Copywriter Fretwell and art director Milbourne began their careers at Saatchi & Saatchi, where they worked on the agency's Army account. Fretwell, a former Campaign Face to Watch, has won awards for Castlemaine XXXX, while Milbourne has won awards for work on The Independent.
They moved to Simons Palmer Denton Clemmow Johnson in 1997, weeks before the merger with TBWA, and worked on Nike, Goldfish, Sony PlayStation and Nissan Micra before moving to Partners BDDH in March 1999.