The Spain international signed an 18-month loan deal with his boyhood club from Milan on Monday, returning to the Vicente Calderon after seven years away.
Torres' move follows a difficult spell for the striker, who failed to discover his best form during three-and-a-half years at Chelsea before another six months of struggle on loan at Milan, who signed the 30-year-old permanently on Saturday and are thought to be close to sealing the signing of Atletico's Alessio Cerci as a makeweight in the deal.
"I'm going to Atletico in search of happiness," Torres said. "As a child my dream was to play for Atletico, and to return is another dream come true.
"[The fans] know it's my home and know that I have felt the sadness of their defeats the joy of their triumphs.
"I have jumped off the couch at their successes and nobody can doubt how I will feel when I pull on that shirt again.
"The Atleti fans always ask that you leave everything on the field and I assure you I will give all that and more."
