Sadly, this day has been coming for a while.

Catherine Willows will disappear for a time after CSI: Vegas Season 2 Episode 12. But it's for a good reason and hopefully is short-term.

Fans of the original CSI rejoiced when Marg Helgenberger agreed to bring back Catherine to CSI: Vegas Season 2. 

Just like with Gil Grissom and Sara Sidle on CSI: Vegas Season 1, having Catherine back has been a blessing. It enables fans to hearken back to the glory days of what was once a franchise.

And frankly, Catherine plays better with the new lab members than Gil and Sara ever did. They came back with a mission: to save the lab's reputation and also Hodges, the fall guy for that season's big bad.

Of course, Catherine did return with her own crusade: to find her missing protege, Grace Huang, which soon morphs into making Grace's killer(s) pay.

Catherine accomplished that goal by CSI: Vegas Season 2 Episode 8. But rather than bidding the lab goodbye at that point, she opted to hang around hoping to improve her relationship with her estranged daughter, Lindsay. 

So what happened in this episode had already been foreshadowed, time and time again. When it comes down to it, Catherine will always choose her work over her personal life. She's never known any other way for years.

You would have thought Catherine could have made some headway when she was slumming it as a casino executive. But apparently the chasm between her and Lindsay was too vast at that point.

Why Catherine thought going back to the place that had originally driven a wedge between them, the lab, would be a good idea was hard to say. She was busy looking for her surrogate daughter, Grace, and was locked once again into work mode.

Her lunch with Lindsay on CSI: Vegas Season 2 Episode 4 must have served as a breakthrough. The two agreed to disagree about Lindsay's social-media-based career choice. But at least they were talking again.

This reunion led to Catherine's day off with her granddaughter, Hannah. Lindsay needed a break from the bundle of energy that is Hannah and Catherine was required to do grandmotherly things. It sure seemed like a good idea on paper.

That is, up until the point that Maxine called in Catherine for a meeting and Catherine brought Hannah to the lab, the very place Hannah's mother had spurned.

Naturally, Catherine yearned for a do-over on a case that the lab had given short shrift to four years prior. That's how she's wired, after all.

Where she went wrong was taking Hannah to a crime scene, however old it was. Catherine has done so much for Penny that she should have asked Penny to watch Hannah instead. But Penny seems too tightly wound to use as a babysitter.

Which led to the younger CSIs (Allie and Chris) juggling their jobs while attempting to amuse Hannah. Let's face it. They were the only ones with the stamina to do so.

Catherine's second big mistake was not telling Lindsay about what happened. Max was right when she told Catherine that of course Hannah was going to spill about her exciting day with Grandma Catherine. How could it have gone down any other way?

Catherine had a revelation after Max explained about the memories of coma patients. She and Lindsay viewed the same incidents from quite different perspectives. And neither one wanted to believe they were at fault in any way.

Fortunately, Catherine realized that she was going to have to be the one who bent. She wanted to be in the lives of her daughter and granddaughter, whose reality has never involved her.

So, Catherine bit the bullet and walked away from the lab ... again. She text-badgered Lindsay until Lindsay gave in and agreed that the three of them could take an extended trip to Hawaii. There are worse fates.

Let's face it: Catherine casts a big shadow. Her short-term absence gives every other character a little more screen time, so longtime viewers can grow to like the new cast.

It's more than halfway through the season and there remain a lot of hanging storylines: The big bad behind the electroshock killings, the Folsom-Serena-Allie love triangle, Max's PTSD.

And let's not forget Beau's decision to stick exclusively to the lab. His kind rebuff of Max showed that he's not willing to change his mind ... yet.

Also, with the fates of CSI: Vegas and All Rise up in the air, Marg Helgenberger can use the time to line up her next gig. She can't disappear from TV again for any length of time.

Still, Catherine will be back, sooner rather than later. This break is just a breather to allow Marg to do other things.

As for the cold case itself, always be suspicious of the most likable among the persons of interest. It was evident from the beginning that Heather popping a mint would mean something and, sure enough, it did.

Most of the others were hideous people (except Sasha's son) but lacked the motive necessary for such a heinous crime.

It was an involving mystery. But its true purpose was to make viewers miss Catherine's expertise during her hiatus.

To follow Catherine's return, watch CSI: Vegas online.

Will you miss Catherine while she's gone?

Will her absence allows others to step forward?

Did you see Max as a hoarder?

Comment below.

Dale McGarrigle is a staff writer for TV Fanatic. Follow him on X.