"It's amazing for us to be part of this thing, but I'm so amazed - a bunch of gadflies we are - to be able to keep 'this thing' secret," said actor Tim Allen.
'This thing' is the last scene of the annual Christmas episode for Tim Allen's sitcom, "Last Man Standing."
The big secret involved a sailor from the U.S. Navy and his return home from active duty.
Petty Officer 1st Class Raymond McKnight joined the cast and crew to try and pull off a major surprise.
His wife and two young sons were told they'd won a contest, and were invited to join other military families to be extras on the set of the show.
The toughest part for McKnight was not sharing the fun with his wife during their ship-to-shore phone conversations.
"I just stopped talking, it's hard for me to tell a lie so I just stopped talking," said McKnight.
The secret stayed safe until tape day and the big reveal.
"Merry Christmas everybody, daddy's home" said McKnight as he jumped out of an oversized present.
"Whenever you get an opportunity to do something like this, you have to jump on it, you know," said McKnight, "I took advantage and said let me do this for my family and myself."
Allen said it was hard keeping the surprise a secret.
"You know you're doing the show, everybody's got to keep a secret from this poor family, you're right in front of all these people, she's got to be surprised, the kids looked shocked - they hadn't seen dad in nine months," said Allen.
"I was a little surprised, I never knew he was coming," said McKnight's 7-year-old son, Julius.
He wasn't sure what was more exciting - being on a TV show or seeing his dad.
"We do a lot of stuff for the servicemen, ABC does anyway, and on this show, we really honor vets, and you get very emotional, at least I do, when you see the reality of being away from their families, service to the country, however you view it, this is a very special breed of men and women," said Allen.
"Last Man Standing" airs Friday nights at 8 p.m. on ABC7.