McGeorge, who has also worked at RMG Connect and Grey Interactive, will be part of G2's management team and oversee all the creative delivery throughout the agency.
In addition, the agency has appointed Mike Forster as client director and Stuart Galvin as senior account manager.
Forster has spent the past seven years working across various global G2 offices. Most recently he has been acting as vice president and regional brand director of G2 Asia Pacific in Kuala Lumpur.
Galvin joins from VCCP and has previously worked with clients including Virgin, Adidas, Orange and Lexmark. At G2 he will work across Nectar and Vodafone.
Tim Hipperson, chief executive, G2, said: "The appointment of three individuals of this calibre will be a fantastic boost to the agency and reflective of the agency's continuing growth and development."