Hearn left the St Luke's London office in 2000 to set up an office for the agency in Stockholm with the planner Anneke Karstedt, but returned in March 2002. That agency has clients including the telecoms company Com-hem and Microsoft Ericsson. It is now under Swedish management and has just started to make a profit, according to Hearn.
Before his move to Sweden, Hearn was a partner with St Luke's creative director, Kate Stanners.
"The 18 months I spent setting up an agency has changed my outlook," Hearn said.
"I wanted to get back to the creative coalface, and TBWA is the perfect place to combine great accounts and fantastic creative opportunities.
It has been great working with Kate, but it is the beginning of a new chapter,
Beattie said Hearn would be a perfect fit for the agency, and confirmed he would start in May. "Tim and Graham will be a red-hot team, and I will be giving them free rein to work on whatever they fancy. They won't be needing any help from me."
He said the two would also act as mentors to the creative department's younger teams.
"Tim is a one-off. He is passionate about advertising and has a no-frills approach - he just wants to get on with the job. In a world dominated by luvvies, he is an antidote and very refreshing,
Beattie added. He said the agency's PlayStation, Hutchinson and the recently won global Adidas accounts would be suitable for the duo to begin working on.
Hearn and Stanners worked together on accounts including Holsten Pils, Cadbury, Boots No 7 and Eurostar. They met at GGT, moved to Bates Dorland and then to St Luke's when the agency formed in 1996.