He joins the agency's creative department to support the creative director, Oliver Green, across all clients, which include Nokia, Pedigree Petfood and Cadbury.
Lusth started out at Razorfish before becoming a senior digital creative at agencies including Grey and DDB in Sweden, where he landed several Cannes Lions.
He was subsequently the creative director and partner at the Stockholm-based ACNE before working in London at Dentsu and Fallon in art director roles. Lusth has also been a lecturer at Hyper Island for the past four years.
Green said: "We are thrilled to have Klas join us. He has the talent to generate world-class ideas across all channels."
Hypernaked was created last year by the merger of Naked Communications with its sister digital agency Hyper. It is the UK office of Naked Communications Global.