# Numbers season 4

The fourth season of Numbers, an American television series, first aired on September 28, 2007 and ended on May 16, 2008. Because of the Writers Guild of America strike, only 12 episodes were initially produced for this season. Following the end of the strike, six more were announced.

## Cast
### Main

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

### Recurring

* Aya Sumika as Liz Warner
* Will Patton as Lt. Gary Walker
* Michelle Nolden as AUSA Robin Brooks
* Leslie Silva as M.E. Ridenhour

### Guest

* Val Kilmer as Mason Lancer
* Chris Bauer as Ray Galuski
* Graham McTavish as John Corcoran
* Yancey Arias as DJ Rodriguez
* Erika Alexander as U.S. Marshal Tricia Yaegger
* Kevin G. Schmidt as Steven Wexford
* Peter Onorati as Alfred McGurn
* Sean Patrick Flanery as Jeff Upchurch
* Ari Graynor as Ella Pierce
* William Atherton as Warren Pierce
* Ben Feldman as Seth Marlowe
* Wil Wheaton as Miles Sklar
* Christopher Lloyd as Ross Moore
* Clifton Powell as Max Devane
* Chris Bruno as Tim King
* Enrico Colantoni as Ben Blakely
* Megan Gallagher as Sarah Blakely
* Aunjanue Ellis as Ivy Kirk
* Julie Dretzin as Karen Griffiths
* Andrea Anders as Rena Vining
* Jill Eikenberry as Susan Doran
* Steven R. McQueen as Craig Ezra
* Gabrielle Christian as Audrey Doran
* Susan Kelechi Watson as Nina Hunter
* Dorian Missick as Derek Raines
* Zeljko Ivanek as William Fraley
* Ravi Kapoor as Phil Sanjrani
* Tiya Sircar as Shaza Rafiq

## Episodes

| No. overall | No. in season | Title | Directed by | Written by | Original air date | Prod. code | US viewers (millions) |
| 62 | 1 | "Trust Metric" | Tony Scott | Ken Sanzel | September 28, 2007 (2007-09-28) | 401 | 9.38 |
| Five weeks have passed since Colby Granger was exposed as a spy working for the Chinese government and after being captured and imprisoned, Colby escapes and along with friend and fellow spy Dwayne Carter (Shawn Hatosy) race through the city, prompting Don and the team to join the search in hopes of recapturing the two men despite the team still struggling to come to terms with the devastating betrayal but all is not what it seems...Val Kilmer guest stars, while Peter MacNicol returns as a series regular. Director Tony Scott makes his American television debut. Mathematics used: Trust metric, set covering deployment, heuristics and Illumination problem ||||||||
| 63 | 2 | "Hollywood Homicide" | Alexander Zakrzewski | Andy Dettmann | October 5, 2007 (2007-10-05) | 402 | 9.76 |
| A girl turns up dead in a star's (Aaron Stanford) bathtub, leading the FBI team to uncover blackmail and murder while following his rescue, Colby rejoins the team. Leigh Zimmerman, Kelly Overton and Steve Kazee also guest star. Mathematics used: Snell's law, Archimedes' principle and game theory ||||||||
| 64 | 3 | "Velocity" | Fred Keller | Nicolas Falacci & Cheryl Heuton | October 12, 2007 (2007-10-12) | 403 | 9.16 |
| When a street race leads to a bad accident in which a man is killed, the FBI find links to a cold case, an unsolved fatal hit-and-run. Chris Bauer (as recurring character Cal Sci engineering professor Ray Galuski), Michael Welch and GQ guest star. Mathematics used: Angular momentum, centripetal force, conservation laws and Newton's laws of motion ||||||||
| 65 | 4 | "Thirteen" | Ralph Hemecker | Don McGill | October 19, 2007 (2007-10-19) | 404 | 9.85 |
| The team is on the trail of a serial killer who tortures his victims the way the 12 apostles died. A Cal Sci Religious Studies professor (Andrea Roth) is brought in to explain the history and the numerology, which Charlie refuses to accept. Sharif Atkins also guest stars. Mathematics used: Fibonacci coding. See also: Numerology and Hebrew numerology ||||||||
| 66 | 5 | "Robin Hood" | J. Miller Tobin | Robert Port | October 26, 2007 (2007-10-26) | 405 | 9.70 |
| A private bank with several suspicious customers is broken into, prompting the team to investigate while David and Colby get their "groove" back as Charlie and Amita discuss her father's reaction to her dating a non-Indian. Will Patton, Tim DeKay, Jason Durr, and Dave Florek guest star. Mathematics used: Listing's law, projectile motion and dating system "Note": The song playing at the beginning of the episode is "Spring and by Summer Fall" by Blonde Redhead. ||||||||
| 67 | 6 | "In Security" | Stephen Gyllenhaal | Sean Crouch | November 2, 2007 (2007-11-02) | 406 | 9.34 |
| A woman in witness protection is killed after going to dinner with Don. The lead suspect is also in witness protection. Charlie's book is released. Guest starts include Erika Alexander, James Morrison, and Peter Onorati. Mathematics used: CART Analysis, Regression Analysis and Path Analysis ||||||||
| 68 | 7 | "Primacy" | Chris Hartwill | Julie Hébert | November 9, 2007 (2007-11-09) | 407 | 9.94 |
| A man is killed while playing an alternate reality game. Amita, a longtime player of the MMORPG side of the game gets put in danger when the killer sees her as his only opponent. Charlie does a TV interview about his book. Charlie asks Amita to move in with him. Guest stars include DJ Qualls and James Urbaniak. Mathematics used: Evolutionary algorithm ||||||||
| 69 | 8 | "Tabu" | Alex Zakrzewski | Sekou Hamilton | November 16, 2007 (2007-11-16) | 408 | 10.26 |
| A big businessman's (William Atherton) daughter (Ari Graynor) is kidnapped, but the whole game changes when he refuses to play along with the kidnappers. Megan deals with her issues with her father again. Sean Patrick Flanery and David Clayton Rogers also guest star. Mathematics used: Tabu search, minimax and Bayesian priors ||||||||
| 70 | 9 | "Graphic" | John Behring | Nicolas Falacci & Cheryl Heuton | November 23, 2007 (2007-11-23) | 409 | 10.12 |
| A comic-book convention becomes a crime scene when a deadly robbery leads to the disappearance of an extremely rare comic book. Guest stars include Wil Wheaton, Christopher Lloyd, Joe Morton and Ben Feldman. Mathematics used: Fractal Dimension Analysis, auction Theory and "Wrinkliness" (Detection of Handwriting Forgery) ||||||||
| 71 | 10 | "Chinese Box" | Dennis Smith | Ken Sanzel | December 14, 2007 (2007-12-14) | 410 | 9.75 |
| A paranoid gunman, revealed to be a former FBI wiretapping subcontractor (Enrico Colantoni), shoots an FBI agent at the FBI headquarters, then shuts himself and hostage David in an elevator. Liz (Aya Sumika) is leaving for a few weeks on a narcotics job. Guest star Chris Bruno is the brother of series regular Dylan Bruno, who plays Colby Granger; Megan Gallagher also guest stars. Mathematics used: Chinese room, "Chomp" and cluster analysis ||||||||
| 72 | 11 | "Breaking Point" | Craig Ross, Jr. | Andrew Dettman | January 11, 2008 (2008-01-11) | 411 | 9.81 |
| An investigative reporter (Susan Floyd) goes missing while Charlie finds that his life is in danger after he tries to help Don and the team solve the case. Chris Bauer appears as recurring character Cal Sci engineering professor Ray Galuski; Damian Young also guest stars. Mathematics used: Regression Analysis ||||||||
| 73 | 12 | "Power" | Julie Hébert | Julie Hébert | January 18, 2008 (2008-01-18) | 412 | 10.08 |
| Don and the team track down an officer (Matthew Morrison) who has turned into a serial rapist. Aunjanue Ellis-Taylor and Andrea Anders also guest star. Mathematics used: Network theory and set theory ||||||||
| 74 | 13 | "Black Swan" | John Behring | Ken Sanzel | April 4, 2008 (2008-04-04) | 413 | 10.00 |
| The team takes down an inner-city meth lab, and while on the bust they also arrest a bystander who is discovered to have guns and other suspicious items in the back of his van. Mathematics used: Floyd-Warshall algorithm, Dirichlet tessellation, brute force and time series. See also: Black swan theory. ||||||||
| 75 | 14 | "Checkmate" | Stephen Gyllenhaal | Robert Port | April 11, 2008 (2008-04-11) | 414 | 9.54 |
| Don's old flame AUSA Robin Brooks (Michelle Nolden) returns to California to prosecute an incarcerated criminal kingpin who seems to be ordering assassinations from within the prison. Don and the team find themselves in a race against time to convince a teenage chess genius (Tequan Richmond) who may be the clue into finding how the orders are being sent. Mathematics used: supervised multiclass labeling, paper folding, diamond cut, chess and algebraic chess notation ||||||||
| 76 | 15 | "End Game" | Dennis Smith | Don McGill | April 25, 2008 (2008-04-25) | 415 | 9.64 |
| Don and his team hunt for an ex-Marine (Sharif Atkins) wanted for murder, while the ex-Marine's family is kidnapped. Bill Nye returns in the recurring role of Charlie's CalSci colleague engineering professor Bill Waldie. Mathematics used: OODA Loop and decision theory ||||||||
| 77 | 16 | "Atomic No. 33" | Leslie Libman | Sean Crouch | May 2, 2008 (2008-05-02) | 416 | 10.33 |
| A cult is poisoned with arsenic, but refuses medical help. Their new leader is trying to change that and other things about his church. When they find that the old leader was also poisoned with arsenic, the mystery gets deeper. Jill Eikenberry, Michael O'Keefe, Steven R. McQueen and Gabrielle Christian guest star. Mathematics used: Bayesian network analysis, Non-Newtonian fluid, social network analysis, affinity analysis and K-optimal pattern discovery ||||||||
| 78 | 17 | "Pay to Play" | Alex Zakrzewski | Steve Cohen & Andrew Dettman | May 9, 2008 (2008-05-09) | 417 | 9.33 |
| A rapper is killed after a celebration thrown by the record label. Megan is taking some time off and Charlie finally meets Amita's parents (Brian George and Gita Reddy). John Paul Pitoc, Dorian Missick, Lester Speight, Richard T. Jones and Susan Kelechi Watson guest star. Mathematics used: String metric and Gröbner basis ||||||||
| 79 | 18 | "When Worlds Collide" | John Behring | Nicolas Falacci & Cheryl Heuton | May 16, 2008 (2008-05-16) | 418 | 9.78 |
| Charlie and the FBI have their differences about the work of a Cal Sci Pakistani scientist (Ravi Kapoor) and a Pakistani charity group suspected of funding terrorism. Zeljko Ivanek and Shawn Doyle guest star Final appearance of: Diane Farr as Megan Reeves Mathematics used: Byzantine fault tolerance, Figure-Ground, Wallpaper group, M. C. Escher, Hyperbolic geometry and Six degrees of separation ||||||||