Sam returns in the March 26 episode - the last before "Smash" moves to 9 p.m. Saturdays April 6 - and he's back with a big solo.
"The song is called ['(Let's Start)] Tomorrow Tonight,' " Odom said in January, before the Season 2 premiere.
"It's an original [Marc] Shaiman and [Scott] Wittman song, which is a dream come true," he said. "To have a tailor-made song, to my key . . . I recorded it in Marc and Scott's house. It doesn't get any better than that. I had a blast."
As for his absence from the show, "it was as hard for me to go . . . as it was for Sam," he said, laughing. "I didn't want to leave. But you know, they had to develop other characters."
Odom, who recently married actress Nicolette Robinson ("Perfect Couples") and who last year was featured in George Lucas' Tuskegee Airmen film, "Red Tails," thinks that Sam's ready to make some changes, too.
"We've seen him be a terrific friend to his partner, Tom, and his best friend, Ivy, and what we see from him this season is more of his ambition for himself, and dreams for himself," he said. "Sam wants to be in the spotlight, too, I think. And that's news to him. Because that's not what he felt last season."
Odom grew up in East Oak Lane, attending Masterman and High School for Creative and Performing Arts, and taking classes on scholarship at Freedom Theatre and Philadanco.
"There was a burgeoning black theater scene when I was coming up," he said. "They were kind of just plucking young guys off the street who had any interest, and they would just kind of, you know, give you training and attention and love, and I owe them a great debt."
He went on to major in theater at Carnegie Mellon, where "Smash" co-star Megan Hilty was a year behind him. But he was just 17 when he made his Broadway debut in "Rent," a show he'd been fixated on since seeing a "20/20" report on it years earlier.
"I heard this great quote, that artists are always trying to get back to the moment where their heart was first opened up," he said. "And that was the show that opened my heart up. I mean, I stood in the HMV music store on Walnut Street and listened to the whole cast album standing up. And paid $20 for the double CD."
Auditioning while still in high school, "I thought, 'I should audition now because I'm not going to get in till I'm about 30. So, I'll meet them now [and] I'll just keep coming back so they get to know me, and then I'll do that show when I'm like 30 to 40, and then retire.' So when I got it at 17, what it did was it forced me to dream a bigger dream for myself."
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