Obsession

Singer and superstar Skyler Wyatt reports a knife-wielding intruder in her home. The break-in seems to be connected to the hate mail she has been receiving for the last three months. Don begins to investigate and the body of a paparazzo is discovered in an area overlooking Skyler's home. Don brings in Charlie to analyze the hand-written hate mail and to try to determine where the strange photographs found on the dead body were taken. As the investigation proceeds the brothers are drawn further into the murky world of the paparazzi and celebrity stalking!

Plot
A woman is swimming in her pool. She answers a ringing phone, but the caller hangs up when she answers. Somebody is behind her with a knife and she runs to another part of the house and locks the door. She calls 911 as the person tries to get in.

Don brings Charlie to the crime scene. It turns out this is the home of a singer named Skyler Wyatt. Don lets the officer taking her statement go as he takes over. She's been getting threatening letters for six months. She didn't report them because she didn't want the press to get a hold of the story and make things worse. Megan briefs the team on the various types of stalkers. She thinks that Skyler has probably made contact with her attacker without realizing it.

They look for, but can't see, the attacker on the security cameras and don't know how he got away without being seen.

Larry shows Charlie and Amita his 'new' car, 1931 Ford Model A Deluxe Roadster. Megan approaches admiring the car. She then asks them if they can help her with the security footage. David and Colby follow up with neighbours to see if they saw anything the night before, but don't get any leads.

Charlie and Larry build a replica of Skyler's house in the Eppes' dining room using cereal boxes. Alan joins them and helps them with their project. When complete, Charlie can't see why the cameras didn't find the attacker. There is an issue with the cameras as it replicates the human eye. The stalker just had to freeze the camera at the right moment and would then be able to get past the cameras without being detected. They find a faint outline of them.

David is running down anybody that has been in the house. Megan thinks she may have found something in the letters. A good candidate would have started stalking her about three weeks previous. Don and Megan meet with her to try to identify who did it. She gets upset by the paparazzi outside her window. As they're leaving, Don notices a DWP van and finds it odd.

Megan meets with Charlie and Larry at CalSci for an update. All he can provide her with is a more distinct outline. Charlie finds a letter at his chalkboard. It's a note from a secret admirer. A photographer named Jerry Wilcox bought a uniform for DWP, but he doesn't work there. David informs them that Colby found him. He's dead in the brush and has been dead since two days after Skylar's attack. He has a perfect view of her home. Megan doesn't think he's the stalker as the behavior doesn't make sense.

David and Colby go and talk to another photographer that Wilcox worked for. He was trying to get shots of Skyler potentially with a lover. Megan notices that Skyler's husband hasn't rushed home to see her. Skyler admits that Dante Baker (the rapper) was supposed to come by and that there was something going on between them, but he didn't show so she went to bed. David and Colby catch up with Baker and his crew at the golf course to ask about Wilcox. He lawyers up. Megan thinks that the stalker could have killed Wilcox if he thought it would put Skyler at risk.

Amita, Charlie, and Larry are discussing the Roadster when Megan comes to get Charlie's help with FISH, a program that analyses handwriting. She goes to admire the car and gets Larry to promise to take her for a ride in it.

Charlie and Alan are holed up in the garage looking at the letters. He compares handwriting to a gymnastics floor routine. Colby comes in for an update. FISH kicked out the name of a man who is in prison in Utah. However, Charlie has discovered that the same person did not write all of the letters.

Colby check in with Don and Megan with Charlie's new information. They rule out the husband and wonder if Baker is at fault. They are wondering why Wilcox would have taken photos of a basketball hoop and where it was. Megan meets with Skyler again to see if she told anybody about the letters. Charlie is pondering his anonymous letter. David comes in to check in about the security footage, but also to take a look at the pictures that Wilcox took. Charlie and Larry help David and Colby find where the hoop is. Baker's right hand man, Orville, answers the door. The security footage has also been cleaned up enough to be able to tell that it was Orville in the backyard. He gets brought in for questioning by Don and Megan. It turns out Dante met with Wilcox to get him to take publicity pictures. Orville was the copycat writer, saying that he only wrote the letters to warn her that she was being used and to scare her. He wanted her to know that she wasn't safe and needed protection so he broke into her home. He denies killing Wilcox. He has an alibi for the night of the murder.

Don and Megan meet with Baker. They have proof that Baker called Wilcox multiple times. He says that Skyler wasn't there the night Wilcox was killed. He drove up to his perch to tell him it wasn't going to happen when he found Wilcox dead and ran away. They meet with Skyler. They have proof that she talked to a tabloid editor friend the day Wilcox was killed. She admits to confronting him and when he wouldn't let her go she grabbed his tripod and beat him until he let go and she ran away. They arrest her.

Alan, Charlie, and Larry talk about the new car and the anonymous letter more.

Main

 * Rob Morrow as Don Eppes
 * David Krumholtz as Charlie Eppes
 * Judd Hirsch as Alan Eppes
 * Alimi Ballard as David Sinclair
 * Navi Rawat as Amita Ramanujan
 * Diane Farr as Megan Reeves
 * Peter MacNicol as Larry Fleinhardt

Recurring

 * Dylan Bruno as Colby Granger

Guest

 * Samaire Armstrong as Skyler Wyatt
 * Johnny Whitworth as Dante Baker
 * David Moscow as Orville
 * Paul Schulze as Photographer
 * Pepper Sweeney as Victor Smith
 * Chase Hoyt as Paparazzi #1
 * Bruce Nozick as Dante's Attorney

Title
Beyond the literal, there is also a sense of celebrity perfumes, like Calvin Klein's Obsession, and similar 'development of the brand'.

Trivia
Larry's "new" car is a 1931 Ford Model A Deluxe Roadster.

Navi Rawat and Samaire Armstrong both starred on The O.C. (2003).

The song playing at the beginning of the episode is "In the Waiting Line" by Zero 7.

Goofs
When Larry and Charlie are talking in Charlie's office and David comes in to ask about the photo location analysis, when David walks into the office, the shadow of the boom mic is visible in the upper right-hand corner of the screen.

When Larry is showing Amita and Charlie his "new" car, his reserved parking sign reads "Cal Sci Mathematics." Dr. Fleinhardt is a physicist, not a mathematician. Even though Math and Physics are usually part of the same division at a university, they are still separate departments.

Crazy Credits
[This appears on the beginning of the episode] 1,000,000 Women Stalked, 170K Celebrities, 4400 Murdered, 1 Obsession