Actually, you have a ready-made Ms. Johnson for just this sort of activity: The Great Feathered Serpent Arleesh. If you have (or have access to) the adventure Bottled Demon (yes, it's for 1e, meddle with it), jump in with that.
Essentially, though, you have a Great Dragon wanting an object destroyed (her objects-du-destruction tend to be severely tainted ones), an adult dragon wanting to use it, and the runners caught in the middle. In your case, however, you might care to have the Third Party be someone else - I like the Atlantean Foundation for this sort of thing, but you can present anyone who you feel is too uppity for their own good. Arleesh is using the runners 'cause that's what she does in order to keep a low profile.
You might also have the group the team is aquiring the object from be sensitive/powerful. Maybe they're hired to steal from Ares - a peculiar focus which allows a standard mage to conjure insect spirits as though they were an insect shaman, and the focus might be one of the reasons why Ares has been able to do what they've been doing in regards to the insect spirits. It's only recently moved into Seattle and which Arleesh has only been able to sense
because of that move, and since Seattle might actually only be a stop-over point, she has to move fast - hence the runners. Ares is going to be hot on their heels, and the other group - maybe the AF, maybe the Draco Foundation (inadvertently trying to recover the thing for Arleesh as well), maybe some dark/toxic/insect mages going after More Power - is chomping at the bit after the thing too.
Make the Johnson they first meet in person (in the Barrens) a local fixer - their fixer says, 'X guy wants to meet', passes you along, that sort of thing. They have to do the run within the next 36 hours, because that's when it'll get moved out of the Ares High Security Warehouse and onto a ship bound for Somewhere Else. Ares has an invested interest in it, so there are mages on staff, keeping an eye on it - and even a mage not on location, keeping tabs on the astral via spirits (or otherwise). Make it virtually impossible to get out of the warehouse district without the alarm going up - maybe a mage (with his bodyguards) arrives to check on the thing just as the 'runners have gotten the goods and are racing out of there, and he, familiar with the cargo, senses its powerful aura through their vehicle.
Running three-way battle into the barrens, with any Ares/KE goons that have gotten knocked off getting readily replaced by cars that have 'caught up' to the pursuit ...

And then, when the players get into the Barrens, blow away the last of the KE cars, and evade the AF/DF/psycho-mages, they can meet with their fixer and <insert gorgeous female SoAm Native American description here>. And when the AF/DF/psycho-mages show up, she can step in (if things are going south) to make sure the people who have done her task don't get blown away.