The forward scored a power-play goal at 14:33 of the second period to give Detroit a 3-0 lead, and an empty-net goal for the 5-1 final.
"I just felt like everything was going fast. I wasn't," Larkin said. "As the second and third (periods) started to happen I felt a little bit more comfortable. It was nice to be on the good side of some good plays, and the power play was clicking. I felt good."
Larkin, the Red Wings captain, missed 12 games last season and did not play after April 20 because of a neck injury.
"I'm not [going to] lie to you guys, I was nervous today," Larkin said. "I had jitters to play. ... I was nervous, not to get injured, just to play hockey. It had been a long road."
Taro Hirose, Chase Pearson and Joe Veleno scored, and Thomas Greiss and Calvin Pickard combined to 19 saves for the Red Wings, who are 3-0-0.
Carson Meyer scored a third-period goal, and Elvis Merzlikins made 18 saves for Columbus.