Anomaly's first work for Diesel since the appointment will arrive in February, consisting of an integrated campaign across TV, print and digital.
Diesel's artistic director, Nicola Formichetti, said the brand was looking for reinvention.
She said: "Diesel’s success rests on its ability to reinvent itself to stay relevant and compelling without being locked in a beautiful past.
"We were looking for a partner that understands the changing consumer landscape, and thinks of innovative solutions beyond advertising, and we found that in Anomaly,"
Anomaly worked with Diesel in 2010 on the "Be stupid" campaign (above). The agency resigned the account after only nine months.