Easy "Star Performer" trophy - Play the San Francisco level in Co-op mode. With another skilled player, you should be able to find all the cards and items quickly enough to earn an "Elite Agent" rank and get the "Star Performer" trophy.

Trophies - Successfully complete one of the following tasks to get a trophy:

Finder's Keepers (Bronze): Find all Items in a City Location.
Quick on the Draw (Bronze): Find 3 items within 5 seconds.
Not Impossible (Bronze): Complete one Mission.
The First Hint's Free (Bronze): Complete one Mission without using any Hints.
Wham, Bam (Bronze): Complete a City Location in less than 30 seconds.
You Always Remember Your First (Bronze): Complete Mission 3 and capture Mister Smith.
Back for Seconds (Bronze): Complete Mission 6 and capture The Hammer.
Third Time's the Charm (Bronze): Complete Mission 9 and capture The Artiste.
Bonus Plan (Silver): Find all Bonus Items in one Mission.
Star Performer (Silver): Earn Elite Agent Rank in any Mission.
Fourth Down (Silver): Complete Mission 11 and capture Dr. Chaos.
Just Said "No" (Gold): Complete every non bonus Mission without using any Hints in single mode.