A "opening sequence" should mostly be "In media reis," which means start in the middle.
The usual spot to start such a scene is right in the middle of the gunfight, or the car chase. No long set up, no long explanations. Just "Here it is, go!" For example:
"Okay, you guys are in a race boat creening down Vience's flooded, swollen canals (just watched Nova, it seems the floating city is sinking). You have a package in plain butcher paper secured to the floor. You have to get it to the safe house -- now! You hear bullets wing and wizz behind you. Who's got the stern covered? Great, you see another power boat behind you with one driver and two guy firing, the suddenly peel away to barely make the 90 degree turn down another canal. Thier manuver reveals ANOTHER power boat chasing you with one driver and THREE gun men. Make a Spot check. You think there may be a third chase boat behind your new pursuers. Okay roll for initiative, and where did that first boat go?"
Then run the combat until the guys lose the Predators (you might want to throw in a helicopter in there somewhere too.) Then the group succesfuly delivers the package and sits down for thier briefing of the real mission. What is in the package is irrelevent.
But make something up if they ask.
You can sometimes do a little more set up (like start with the group successfuly stealing the package out of the safe and then cleverly exiting the building from the roof to land in their boat.) But the more you add, the more the device becomes a drawn out introduction than as a adreliene pumping tease.
And don't worry, your player won't mind this technique of starting in the middle of combat because they should be aware that is part of the genre. I run a Farscape game and when started an episode with everyone in the middle of a starship combat, the group didn't bat an eyelash. They simply said, "Yep, this is a TV series all right" and picked up the pieces of the ambush.