<EM>CSI: Miami</EM> CSI: Miami

Every once in a while, David Caruso will come upon an early episode of CSI: Miami on A&E and just shake his head. "We're all so much younger, our voices are higher, there's not a line on anybody's face," he says. "Now you see us and we're these world-weary warriors carrying the weight of all these crimes." Five seasons in, the Miami unit "has been through hell and has the baggage to prove it," he says.

But there's an upside, at least for fans. All those battle scars lead to a level of emotional depth the show didn't have a few seasons back. And in tonight's episode (10 pm/ET, on CBS), it's clearer than ever that those emotions are right on the surface.

In the first half of a two-parter, the lives of two CSIs are on the line when Horatio (Caruso) goes head-to-head with Clavo Cruz (Gonzalo Menendez), a killer he put away in Season 3. The episode ends when a veteran member of Horatio's team is shot.

"We're faced with things we've never been faced with before," says Adam Rodriguez, who plays CSI Eric Delko. "What happens wakes everybody up to the fact that these guys can't win every time." If it's worse than when CSI Tim Speedle (Rory Cochrane) got killed during a case in Season 3, this must be bad.

Suffice it to say, you're in for an old-fashioned cliff-hanger that begins with a dark ritual. Once a year, the Miami-Dade Police Department rounds up all the weapons it's collected from bad guys and brings them to the "gun melt," where they're turned into sheet metal. But when the "dispo" truck is hijacked and looted, it's suddenly all-you-can-eat day at the free-gun buffet. With the illegal guns back on the streets, it's up to Horatio's unit to play cleanup. That's when H. pegs the crime to Clavo, who's been sprung from prison.

"With Horatio and Clavo, we're dealing with two characters who have history, which makes the chess game they're playing all the more tantalizing," says executive producer Ann Donahue. As for who takes the bullet, she says, "It may be the most traumatic event the team has ever dealt with." Ah, more ambiguity.

What we can tell you is that there are more juicy cases coming up after this two-parter. One involves a "mancation" — a vacation for a bunch of guys — filled with liquor and big-game hunting in the Everglades. But as it turns out, the women back in the South Beach clubs are more dangerous.

Sounds like H. is about to get more lines on his face.

For scoop on another CBS procedural, Cold Case, pick up the Feb. 5 issue of TV Guide.

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