The CSI team investigates two unusual cases, one involving the suspicious death of a go-cart racer who took his hobby to the highway and paid the price with his life, and a murder at a hip new restaurant where patrons dine in the dark

A patient is in the hospital because they fell asleep in a hazardous situation. A patient's home laboratory blew up in an apartment building and the victims flood the hospital. Alex investigates the cause of the incident by talking to a really old guy who lived in the building. Jane Burke shows up to deal with what her son left behind. Lexie tries to talk to Meredith. Callie is overwhelmed by her new position while Bailey is searching for things to do.

The gang agrees to sell Paddys when they get an offer that is too good to refuse, but it forces the bar's non-partners, Dee and Charlie to find new jobs.

Mac teams up with Frank and Charlie to create a public access newscast after he misses his chance at fame in the news. Meanwhile, Dennis and Dee try to make it big in the club scene.

Nicolette Sheridan, Tony Snow, and Rihanna are the scheduled guests.

Peggy is given a difficult assignment. Roger's work problems provide new opportunities for Don, and Pete grows more frustrated. Betty finds a new outlet for her growing dissatisfaction.

Seven demons, based on the Seven Deadly Sins, are released into the world and the brothers must combat them with the aid of a married Hunter couple.

Episode info coming soon ..

Ryan returns to his old office and reveals his plan to bring technology to Dunder Mifflin. Michael and Dwight try to prove that the personal touch is better than technology. Meanwhile, Jim and Pam reveal their relationship to the rest of the office, Kelly attempts to reunite with Ryan, and Dwight and Angela's relationship continues to plummet.

In a special hour long episode, Ryan returns to Scranton with a plan to bring Dunder Mifflin into the digital age by launching a new website - Dunder Mifflin Infinity. Michael is worried about ageism and attempts to win back clients using old fashion business skills. Relationships are on the forefront as Ryan returns to an eager Kelly, Jim and Pam are outed to the office, and Angela is still upset with Dwight about her cat.