"Of Mouse and Man" is the ninth episode of Season 1 of Grimm and the ninth episode overall. It first aired on January 20, 2012 on NBC.
An angry man enters a parking garage and yells at someone. He chases the other across the garage and a few seconds later is dead from having a screwdriver driven into his throat. However, his appearance has changed to that of an older man. A hooded figure drags the body to a dumpster, which is later emptied by a collection truck. Nick and his partner go to the site where the body was dumped, they then find Natalie Haverstraw, the woman who was being abused.
They interview her, she is shocked to find out Leonard is dead. She says that Lenny had been drinking and they got into an argument. That is when Marty, another tenant, came to see if everything was alright. Lenny started yelling at Marty, when another tenant, Mason Snyder showed up. Marty left and Lenny and Manson's argument got heated. She had Mason escort her to her car to leave after she got her stuff.Nick and Hank then go to the junk shop Marty owns to hear his take on the argument. He says almost the same story as Natalie says, and says his dad can verify that he returned to the aparment after the argument. During the interview, Nick sees Marty morph into a mouse-like creature. Next Nick and Hank visit the law offices of Mason Snyder. While Mason gets into an argument on the phone, Nick sees him morph into a snake-like creature.
Next Nick visits Monroe to learn more about the snake and mouse creatures. Monroe says Mauzhertz are very meek and afraid, and one rarely meets a Lausenschlange and lives to tell. Monroe suddenly gets a call to repair an old clock tower the next day at 12:30. Monroe then leaves Nick to think about these new creatures.
Juliette Silverton arrives home and sees a woman in a pick up truck photographing the house. Juliette writes down the license number of the truck and tells Nick. He learns thazt the truck is registered to John Oblinger.
Later an unknown man is at a repair shop, he is upset with the owner about the outcome of his car repair job. The owner, Andy then yells "Then take me to court!" The shop owner then morphs into the same old man at the parking garage. The unknown person then kills him and dumps his body in the dumpster. Nick and Hank discover the body the next morning. They think the two cases are connected. After looking at the shop owner's recent customers, they discover one of them is Marty.
At around noon, Monroe arrives to fix the clock tower. He discovers no one is at the location. He sees someone on the balcony, when he looks up people attack him. Before he gets knocked out he realises he is being attacked by Wesen.
Juliette goes to the address at which the pick up is registered. She sees the woman who rushes two children into the house.
Marty meets Natalie as she is moving the rest of her belongings. Natalie tells Marty that she needs to leave town and start over. Mason comes out with boxes of Natalie's belongings, and Marty leaves.
Nick and Hank then go into Marty's cluttered aparment, there they find Marty's Father, dead. He has been dead at least a few days. Marty then goes to attack and kill Mason, Nick and Hank arrive later and realise Marty is dangerous and at large. Marty then meets Natalie with flowers and an invatation to dinner. Natalie, surprised by Marty's new personality, agrees. At dinner, Marty is giving Natalie positive complements when an argument between a father and his son interrupts. Marty then punches the dad, Natalie has to drag Marty out of the restaurant. As they leave, Marty sees every man as his dad.
Marty then speeds off with Natalie in his Camaro. Natalie appears frightened. The police start chasing him, before they lose him as he goes to his shop. At the shop, Marty drags Natalie into the shop. Nick and hank then find Marty holding Natalie hostage inside the shop. After taking Natalie to safety, Nick tells Marty his father is dead. Delusional Marty tells Nick he sees his father everywhere, no matter how many times he kills him. Nick arrests Marty.
Juliette tells Nick about having "investigated" the woman.
Afterwards, Nick visits an injured Monroe, who found a reaper symbol on his car after he got beat up. Monroe says the Reapers attacked him because he was helping a Grimm. Nick says he won't ask Monroe for help. Monroe objects; he vows to stick with Nick and be ready for any future attacks.
- During times of stress, Martin Burgess sees a number of different people, including himself reflected in a mirror, as images of his father.
- "The White Snake" is a German fairy tale collected by the brothers Grimm, but does not contain the quote.
- The title is a reference to the John Steinbeck novel, Of Mice and Men. Like the episode, the book has a socially awkward character who is pushed to violence and both were fond of mice.