Ridd will work across the agency's entire portfolio, reporting to Steve Hastings, planning partner for the agency.
Ridd joins Isobel from sister VCCP agency SFW, where he worked as senior planner across a number of accounts, including Southern Railway and MORETH>N, for which he led the strategy on the MORETH>N FREEMAN campaign.
Before working for SFW, Ridd was at Kitcatt Nohr Alexander Shaw for three years, where clients included Waitrose, John Lewis and the NSPCC.
Hastings said: "Chris is an important hire in strengthening our senior team and planning capability, and brings with him a wealth of experience with some impressive campaigns under his belt."
In January, Isobel won the £5m Jackpotjoy account, beating M&C Saatchi, DraftFCB and Creature in a competitive pitch.
Isobel has also worked with Bernard Matthews, Werther's Original and Kettle Chips.
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