“Grimm” Season 5, Episodes 21 and 22 will air back-to-back as the season finale on May 20 on NBC. Titled “The Beginning of the End” (Parts 1 & 2), this year’s finale is expected to be a monumental event involving Black Claw, Hadrian’s Wall, Sean Renard (Sasha Roiz), Nick Burkhardt (David Giuntoli), two grown-up Hexenbiests -- Eve/Juliette (Bitsie Tulloch) and Adalind Schade (Claire Coffee) -- and the powerful little 'biest, Diana (Hannah Loyd).

Spoiler alert: This update contains “Grimm” Season 5 spoilers. Details include synopsis of the finale episodes as released by NBC. In this synopsis, something happens to Hank (Russell Hornsby) that greatly affects Nick. Meanwhile, Eve tries to avoid thinking of what Juliette would feel in Nick’s crisis now.

UPDATE, REVIEW: The fifth season finale of "Grimm" has to be one of the best and brilliant chapter enders this year. Norberto Barba's take on Nick's biggest fight ever in the series is nothing short of masterful. The ending leaves a lot of new questions, and the show is in good position to build a new world with new complexities and possibilities. Season 6 (officially confirmed by NBC) may not be the last Grimm season, after all. Bitsie Tulloch is fantastic in the last few moments of the season. A year ago, she was ready to kill Nick in a dazed and confused state. Now she feels "a lot" again, suggesting Juliette was dead, but she is back -- perhaps for good!

RELATED: Bitsie Tulloch leaves ‘Grimm’ but stays in-love with David Giuntoli

Detective Hank Griffin vs Black Claw: His death is possible, unless --

“Black Claw makes a strategic move against Hank that shocks everyone and sends Nick (David Giuntoli) on a war path,” reads the Grimm 5x21 synopsis from NBC. In the previous episode, Hank learns that his revived romance with Zuri Ellis (Sharon Leal) was all part of Black Claw’s plan. Based on the synopsis, something bigger is coming to Hank and Nick is going to lose it. Will Hank die in “Grimm” Season 5 finale?

Some fans are convinced that Hank’s death could be the showrunners’ move this year to further justify the unleashing of wrath from Nick’s very core. “Grimm” creators -- Stephen Carpenter, David Greenwalt and Jim Kouf – delivered the death of Juliette in the Season 4 finale, but she did not really die. Bitsie Tulloch’s Eve has some very real Juliette tendencies, i.e. protecting Nick in his personal affairs and threatening Adalind against hurting Nick.

RELATED: ‘Grimm’ Season 5, Episode 19 Promo Video: Diana as 3rd Hexenbiest in ‘The Taming of the Wu’ (Review, Spoilers)

Then again, Nick and Trubel (Jacqueline Toboni) have a centuries-old magic stick that could be even more powerful than a hand of god in The CW’s “Supernatural.” At this point, no one knows if it could resurrect anyone – just that it carries with it “peligro” and “milagro” (peril and miracle).

Half-Zauberbiest vs Grimm: Frenemies become full-on warriors from opposing teams

NBC’s promo video for “Grimm” Season 5, Episode 21 shows a big fight between Sasha Roiz and Nick Burkhardt -- the former is on his half-Zauberbiest Wesen mode, while the latter is attacking like a beastly grimm, ready to kill the new mayor of Portland in his old police captain’s office!

The NBC promo video also mentions nothing from the second part of the “Grimm” Season 5 finale is included in the clip. What it does show aside from the Burkhardt vs Renard fight, is little Hexenbiest Diana, controlling dad Sean and mom Adalind like puppets in a romance show. In the previous episode, Diana sends her baby brother Kelly levitating over their heads, sending chills to Adalind.

Trubel is also in the fifth season finale teaser, upset that there is insufficient manpower in their fight against Black Claw, which is apparently headed by the disturbingly mysterious Conrad Bonaparte (Shaun Toub). In the previous episode, Bonaparte is revealed to have been working closely with Zuri to fool Hank into letting his guard down.

Black Claw’s Conrad Bonaparte vs Hadrian Wall’s Eve/Juliette and Trubel

Bonaparte has also ordered his men to follow Drew Wu (Reggie Lee), aware that the sergeant has become a werewolf by Wesen infection. Could Hank be a red herring in the synopsis, while Wu is the character who dies in Grimm’s fifth season finale?

About a month ago, David Giuntoli expressed some doubt over NBC’s order for “Grimm” Season 6. He may have known enough at the time to be in such a place where he could accept this finale as the last ever.

RELATED: ‘Grimm’ Season 5, Episode 18: Wu expected to transform, Season 6 could be last

Eve may not be willing to act like the emotional and vulnerable Juliette again, but now that Nick is in grave danger, how long could she hold back? Here are some interesting lines between Trubel and Eve from “Grimm” Season 5, Episode 20 (“Bad Night”):

Eve: Does he blame Adalind?
Trubel: No, he thinks she didn't have a choice.
Eve: What do you think?
Trubel: No, what do you think?

Eve: I think there is a choice even when there appears to be none, but it's the reaction that determines whether the choice is good or bad, not the person who makes it.
Trubel: And what would Juliette think?
Eve: I don't go there. Too dangerous.

WATCH: ‘Grimm’ Season 5, Episode 21 Promo Video (NBC on YouTube)

“The Beginning of the End” (Parts 1 & 2) also stars Martin Meisner (Damien Puckler), Blutbad Monroe (Silas Weir Mitchell) and Fuchsbau Rosalee Calvert (Bree Turner). At this stage, Bonaparte’s Wesen nature is still unknown. He, however, seems a lot more powerful than Renard’s father, the late King Frederick, a human.

“Grimm” Season 5, Episode 21 was written by show bosses David Greenwalt and Jim Kouf, and directed by Greenwalt. The second hour was written by actor/director Thomas Ian Griffith, who also wrote “Eve of Destruction” and “Key Move,” which are both landmark episodes this year. Norberto Barba, who also teamed up with Griffith for ‘Clear and Wesen’ directed the final hour.