updated 05/26/2011 AT 9:00 AM ET
•originally published 05/26/2011 AT 10:15 AM ET
“She doesn’t know I’m here. I pulled a fast one on her,” Duhamel, 38, quietly told PEOPLE backstage before helping to honor Fergie, 36, with the New Celebrity Fragrance of the Year award for her Outspoken scent for Avon.
Duhamel then strolled on stage to introduce his wife – and, knock on wood, future mother of his kids – much to her amazement.