Golik joins from Rapp where he was group executive creative director since 2015 and worked on award-winning campaigns for PayPal, Virgin Media and Heist.
Before Rapp he spent 10 years at Kitcatt Nohr, working on Waitrose, Nando's and Starbucks.
Thomas left the agency after 18 months and without a job to go to. He replaced Nicky Bullard who was made chairman of MRM Meteorite.
Golik said: "The agency has everything needed to raise the bar for creativity for our industry – the brightest people, a fantastic can-do culture and a massive level of ambition."
Reporting to Lida chief executive Victoria Fox, Golik assumes overall leadership responsibility for the agency's creative output. After Thomas' exit, Lida's executive creative director Tori Winn had held this role.
Of Golik's appointment, Fox added: "Creative flair and step change thinking is needed more than ever to ensure our whole industry is loud and proud about the unique ability we have to solve marketing challenges for clients. Ben is, quite simply, a star and we can’t wait to get working with him."