Is he asking to get Zonked?
1] "Nancy Drew"
This was Mary's name for her partner Marshall's girlfriend Abigail, the detective from the Albuquerque Police Department.
Nancy Drew was a teen-aged amateur sleuth who first appeared in the literary universe (Word-World?) in 1930. Decades after a few forays into the Cineverse, Ms. Drew became part of Toobworld in 1978. Any appearance beyond 1979 would be of a Nancy Drew from alternate TV dimensions.
Thirty plus years on from that point, Nancy Drew probably drew (Sorry about that, Chief!) national attention to herself for solving some crime - perhaps one that put the entire country at risk. This could splain how Mary knew about her.
But then again....
In 1979, Nancy Drew's physical appearance suddenly changed. (Outside the box, this was due to recasting - Pamela Sue Martin originated the role, but suddenly quit when her episode order in the rotation with the Hardy Boys* was drastically reduced to mostly guest appearances in their episodes. She was replaced by Janet Louise Johnson, without any comment about her change in appearance by those around her. Although no one seemed to notice at the time, perhaps the truth was eventually revealed and caused a media sensation which Mary would have read about.
Twice Mary called Marshall by the name of this famous police detective.
Everybody in the real world has a counterpart in Toobworld. Frank Serpico is one who actually got a televersion visible to the Trueniverse audience. But Mary was referring to David Birney's portrayal in the TV series, but as the real cop, not a TV character. If she was referring to any fictional portrayal of Serpico, then it would be to Al Pacino's role in the movie, which was made in Toobworld as well. (Since Serpico was played by Pacino and not Birney in the movie, the movie cannot be absorbed into the Toobworld Dynamic.)
3] "The 'Law & Order' boxed set"
Abigail gave the complete series to Marshal as a gift.
This should be a Zonk! 'In Plain Sight' and the 'Law & Order' franchise should be sharing the same TV dimension. In fact, Mary made a quick cameo in an episode of 'Law & Order: Criminal Intent'.
But the Toobworld Central splainin is that mentions of 'Law & Order' are most likely to a reality documentary series which followed the detectives of the 27th Precinct around on their cases 24/7; a series which proved highly popular. (And Abigail must really love Marshall in order to get him the complete series. I'm not really sure if the same holds true for Toobworld, but that warhorse ran for 20 years in the real world. A complete boxed set is a hefty investment! I think it runs about $700.00....)
4] "Norman Bates"
Mary called Marshall "Norman Bates" after he referred to her as "Mother".
He's much better known for the original "Psycho" directed by Alfred Hitchcock and then for the two sequels, but Norman Bates is a citizen of Toobworld as well. And since Anthony Perkins played him in a TV movie (with Henry Thomas playing young Norman), those first three "Psycho" movies can be excised from the Cineverse and absorbed into the Toobworld Dynamic.
(And, of course, the Vince Vaughn remake goes to some other movie world. If there's a Cinematic Evil Mirror Universe......)
So even though Norman Bates is a fellow TV character, Mary could still know all about him. He probably had the same notoriety as had John Wayne Gacy and Jeffrey Dahmer in the real world. Plus the original "Psycho" movie, even though it can be considered real-life events in Toobworld, was still made by Alfred Hitchcock in the early 1960's. (So much was made of its existence in an episode of 'Murder, She Wrote' that we can't ignore it.) Therefore, TV's Hitchcock was making a docudrama based on fact.
Norman Bates also exists in Skitlandia, thanks to the 'Saturday Night Live' sketch about the Norman Bates School of Motel Management. That episode of the show was hosted by Anthony Perkins......
As for the Norman Bates who mentored young Alex West in the asylum, as seen in the TV movie "Bates Motel", he was delusional and only believed himself to be the famous murderer.
When 'In Plain Sight' eventually returns, I'm sure Mary Shannon will be spouting plenty of other Zonks which we'll have to disable. Hopefully in doing so, we won't wake the baby....
* Because I didn't want to take anything away from the main focus of this post, I'm not getting into the Zonk about the Hardy Boys themselves. They originally appeared back in the 50's on TV, but it's their 70's incarnation that is better known. And we can't have that version of Nancy Drew in the main Toobworld if we banish the later Frank and Joe.
So why not keep both versions? The Hardy Boys of the 1950's were the real deal, and as for the brother sleuths of the 70's? Oh, I don't know - off the top of my head I'll say alien recreations. It could splain why they showed no surprise when Nancy Drew suddenly changed her appearance....
Like I said, I don't even want to bother thinking about that right now!