Navi Rawat and David Krumholtz, <i>Numb3rs</i> Navi Rawat and David Krumholtz, Numb3rs

After overcoming multiple kidnappings, outside entanglements and disapproving families, Numb3rs' Charlie (David Krumholtz) and Amita (Navi Rawat) are finally getting their happy ending.

But the couple's long-awaited wedding in Friday's Season 6 finale (10/9c, CBS) is overshadowed by the ever-growing possibility that the show won't be back after the honeymoon's over. Earlier this season, CBS' math-driven procedural had its episode order reduced by six hours. The result:  Writers scrambled to produce an ending that could double as a series finale.

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The wedding kicks off the episode, leaving plenty of time to solve one potentially last crime. Don (Rob Morrow) loses his gun when making an arrest, and it's used soon after in a double murder. Despite Don's protestations, Charlie insists on helping his brother find the gun.

"Charlie is not going to get on a plane knowing that somewhere out there, someone is carrying around his brother's gun," Krumholtz says, adding that Charlie is also torn about leaving behind his work with the FBI. "Charlie is concerned with passing the torch to someone and not leaving the FBI in a lurch. Charlie's emotional journey is really more about looking back on the work he's done for the FBI and seeing how it's changed him. It's about making peace with it and moving on."

Charlie ends in a good place with Don as well. "In the beginning, they were two brothers on opposite ends of the spectrum, not really understanding each other," Krumholtz says. "The FBI work over the years has brought them together and given them a mutual arena [in] which to find camaraderie and form a bond. Nothing's really different: They're still brothers who hang out with their dad a lot. Everything's pretty much the same, except so much has changed. That's life and it's a nice sentiment."

Closure is evident in most every story line, including those of Larry (Peter MacNicol) and David (Alimi Ballard). And a familiar face turns up for a goodbye salute.

"The episode kind of lets you know where these characters will be and how they end up," Navi Rawat says. "So if the series is canceled, it's not going to be a shock. It's nice for our fans, because I think they will get a sense that these people will go on and have a happy life and get better from everything they've learned over the years."

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