On The Rookie Season 2 Episode 17, Officer Nolan got thrown into the deep end with an undercover assignment and managing his criminal informant. 

Only one of those things turned out to be a success.

One of Nolan's greatest strengths, his empathy, can also be a weakness, or at least an added obstacle. That sense of empathy allowed him to encourage Bianca to get clean and get a job. 

Unfortunately, it also made it easy for her to get too attached. 

Junkies aren't generally emotionally stable to begin with, so Bianca forming an unhealthy attachment to Nolan shouldn't have been a surprise. 

But this was Nolan's first C.I., so it was all unchartered territory for him. 

The upside was that Sgt. Grey understood what Nolan was dealing with and went out of his way to be supportive.

Think back to The Rookie Season 1 Episode 1 to realize the leaps the professional relationship between these two men has taken. 

Sergeant Grey: I will haze, harass, and humiliate you every chance I get in the hope that you will abandon this misguided quest.
Officer Nolan: And If this job actually is my calling?
Sergeant Grey: Then nothing I do to you will matter.

• Permalink: Then nothing I do to you will matter.

It's almost hard to recall how hostile Sgt. Grey was to Nolan when he first arrived from the academy. I certainly wouldn't call them friends, but Grey offering to buy Nolan a beer was something the man who threatened to haze and humiliate the rookie never would have done. 

So much has changed in less than two seasons. 

Bailey Chase guest-starred as Agent Michael Banks, and what is it about this actor that he so frequently pops up as a TV law enforcement officer? Is it the square jaw? The haircut? The overall demeanor?

Certainly most Castle fans will remember him as FBI Agent Will Sorensen towards the end of Castle Season 1. 

Agent Banks getting in Nolan's face over using Bianca was understandable. Banks had a lot riding on this operation, and he saw Bianca as his best means to a successful end.

But I was happy that Nolan didn't hesitate to stand up to him, even when Banks threatened the rookie's job. 

What bugged me more was when Banks cornered Harper in the surveillance truck and intimated that the two of them should have hooked up before this, even though she was married the last time they'd met. 

I saw that as a huge character flaw, and it made me wish Harper had blown him off completely instead of suggesting she was willing to see him again. 

I was also disappointed when Harper's undercover persona, Crystal, was blown. It's impressive and incredibly entertaining getting to watch this actress transform from a tightly controlled police officer into junkie Crystal in the blink of an eye. 

Nolan wasn't half bad at playing her "old man," either. 

My one pet peeve from this whole operation was the surveillance truck. A big, box, diesel truck parked on a residential road at night is going to catch someone's attention. I know I'd take note of it, and I'm not a drug dealer on the lookout for anything suspicious. 

Back at the precinct, Nolan had a point about police officers having a more personal community presence. 

In small towns, people see their officers more often and even in a big city like New York, there are far more foot patrols, but in Los Angeles everyone drives everywhere, including the police. 

So Grey pushing his officers to get out of their shops and walk a beat made sense, even if most of them hated it. 

Nolan: I can tell what you’re thinking.
Harper: Doubt it.
Nolan: You’re working out how to kill me without your body cam catching it.
Harper: Yeah, actually, that is what I was thinking.

• Permalink: Yeah, actually, that is what I was thinking.

The only surprise concerning Lopez paying off dispatch to send her and Jackson the first real call that came through to get them out of their socially active policing campaign was that Bradford didn't come up with it first. 

Det. Calderon's animosity towards Lopez made little sense since the two woman didn't appear to have met before, and I'm glad that Lopez didn't put up with Calderon bad-mouthing Wesley for doing his job. 

Calderon even appeared to do a half-assed job on her current case. She was far more interested in an easy close than with doing the investigative work to make sure she was arresting the right suspect. 

It seemed a little implausible that Calderon would go from despising Angela to offering to help her make detective quite so quickly. Most people aren't capable of putting that kind of animosity aside that fast. 

Last season, Lopez's sole focus was on becoming a detective and her enthusiasm led to tunnel vision and caused her to make serious mistakes.

But Officer Lopez has learned from that. She's more balanced in both her personal and professional life and ready to move forward in her career.

I'm just not sure where that will leave Jackson. 

It was good to see Jackson and Sterling once again; they make a cute couple, and it was nice that Sterling didn't seem overly upset about Lucy barging into their date night.

Jackson was right to confront Lucy about her behavior, and it made her face her fears about taking a chance on dating again.

And who wouldn't be terrified after the last person you dated drugged you, tattooed you, and stuffed you into a barrel to suffocate to death?

As it turns out, Lucy wasn't the only one dealing with the aftermath.

Bradford: The last time I gave you romantic advice I pushed you towards Caleb and you almost died.
Lucy: That’s ridiculous. There was no reason to suspect anything. What happened…what happened wasn’t your fault.
It wasn’t mine either. Look, I wouldn’t ask your advice if I didn’t value your opinion.

• Permalink: That’s ridiculous. There was no reason to suspect anything. What happened…what happened...

Lucy and Tim have become real friends, and I love that dynamic between them. Many fans want to see it progress to a romantic relationship, and I wouldn't mind that -- eventually. 

But for now, I'm really enjoying them just as they are, and if that moves towards something more personal, the slow road might be the most satisfying. 

So what did you think TV Fanatics?

Should Harper go out with Agent Banks?

Was Bradford right about Lucy deserving someone better than Emmett, or was there a hint of jealousy in that comment?

And is Lopez ready to become a detective?

Give me a shout out by hitting that BIG, BLUE, SHOW COMMENTS button down below, and then check back in for my review of The Rookie Season 2 Episode 18.

Until then, you can watch The Rookie online here at TV Fanatic.

C. Orlando was a TV Fanatic Staff Writer. Follow her on Twitter.