The duo will report to creative director Nicky Bullard.
Before joining the direct agency, O'Carroll and White freelanced at agencies including CMW and Antidote. They had previously worked at DDB across key clients such as VW, Harvey Nichols and Tropicana.
Paul Grizzel is also joining the team from AMV as senior digital art director and Laura Buckenham, who has worked at agencies including DDB and Rapier, has been hired as a copywriter.
Other hires include writer Laurence Bushell and digital designer Thomas Lesselliers, both from AIS, and designer Tom Widdrington, from Gyro.
Bullard said: "We have high creative ambitions this year and Andy and Spencer, for example, are the perfect fit for us – ridiculously talented, genuinely integrated and most definitely hungry to take the work to an ever higher level."
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