Sharon in the first half of "Return to Sender." We almost always see her behind a desk. Now we see her run (barefoot!) down eight flights of stairs and then break down a door with a fire extinguisher to save Rusty from the person who's been threatening them.
Provenza in "Return to Sender, Part 2." Rusty's stalker has gun to a kid's head, using him as a Human Shield. It's Provenza who takes him down wit a perfect Boom, Headshot.
Also, the way the LAPD shut down traffic, trapping Rusty's stalker, was truly awesome.
Rusty has one while testifying in "Return to Sender, Part 2." The letters his stalker sent him were initially ruled inadmissible, and Rusty and Rios were instructed by the judge not to speak of them further. Later, Rusty tells Stroh's lawyer that his psych evaluation was related to a lie that he'd told Sharon but he can't tell her what the lie is when she asks. The judge commands him to answer. The lie? The letters. Which means that they are now evidence.
Rusty's response to his sickeningly manipulative addict mother when she tries to guilt him into doing her favors. She has the gall to blame him being gay for her appalling treatment of him, and when she tries to play that card again (trying to get Rusty to pick her up from a bar she got drunk at immediately after leaving rehab, he finally tells her off: "Your addiction is not my fault. Go back to rehab, start over." And he hangs up on her and refuses to answer any more calls from her.
Fritz returns just in time to get one for his handling of a diplomat. The diplomat keeps invoking his right to immunity to circumvent any kind law-breaking, with the team helpless to stop him. Fritz in particular spends most of the episode trying to keep the piece and not upset the diplomat. But when said diplomat takes immunity as far as assualting his own daughter in the middle of the squad room, with a group of officers to witness, Fritz finally takes the man out in a satisfyingly violent way. And when the diplomat threatens repercussions, Fritz counters with deportment for committing a terrorist act inside an American Police Station.