Stagwell, a marketing and communications group, completed the acquisition of Sidekick, a collective of specialist agencies focused on experiential, digital storytelling, and branded content. Financial terms were not disclosed. "Sidekick is at the forefront of storytelling and will be an essential part of the challenger marketing network we are building in Europe. As we embark on our next chapter in Europe, I'm excited to welcome Duncan and Ollie to our network and see Allison continue to transform its content innovation capabilities," Mark Penn, Stagwell Chairman and CEO.