The agency is ramping up the department after a sustained new-business drive during the past year, which saw it pull in accounts including Lloyds and Lego.
All three planners will report in to MT Rainey, the agency's joint chief executive.
Garbhan O'Bric joins this week as a board account planner from HHCL & Partners. He will work on News International and Virgin Trains.
O'Bric joined HHCL in 2000 to take planning responsibility for Guinness Ireland, Yorkshire Water and Cashels Cider. Before that, he worked at Leo Burnett, where he was responsible for youth planning on McDonald's and Heinz.
Lucy Edge also joins as a board account planner, with responsibility for the Marks & Spencer account. Edge joins from Abbott Mead Vickers BBDO, where she spent the past five years as a group head. At the agency, her remit covered Yellow Pages, Famous Grouse and the Tobacco Education Campaign.
The agency has also hired Megan Thompson from DFGW as an account planner on M&S and Quaker.