Part 1 of 2. The Northwest regional qualifying round challenges the athletes.

Conclusion. The Northwest regional qualifying round challenges the athletes.

Board a virtual space ship to travel along with a variety of comets; long and short period, sun grazers, comets masquerading as asteroids and comets still in deep freeze in the Oort cloud. Then ride along on the NASA probes that visited nearby comets.

The Brown brothers are coming to town! Kody ditches his four wives for his three brothers as they hit up the city of sin. They're cruising on motorcycles, hanging out at a biker bar, and shooting guns.

Logan, Mariah, Madison, and Hunter head back to Utah to visit their family and friends, but more importantly, to visit the happy home they left behind.

Kris gets pestered by Bruce to sign his son, Brandon, to her new music management company. Meanwhile, Kourtney doesn't appreciate Scott's romantic gestures and Kris tries to get the whole family to play tennis again with disastrous results.

Adam and Jamie test an old dueling myth - should you really never bring a knife to a gunfight? Kari, Grant, and Tory find out if a two-stage missile known as the fire-breathing dragon ever really existed.

Sookie and Lafayette deal with the aftermath of Tara's encounter with Debbie Pelt. The Vampire Authority makes a call on Bill and Eric. Alcide and Sam are faced with an angry werewolf pack.

Things get out of control in the emergency room due to the recent firings and an overflow of patients who have been diverted from another hospital, causing Cruz to suffer a pulmonary episode and Jackie to step in. At home, a rebellious Grace refuses to go to class unless Jackie transfers her to public school.

A 16-year-old video-game genius sues his father; Kim represents her dad in an eviction case; Stacy and Nikki decide to go into business together; Luke becomes more involved in Jane's personal life than she would like.

A beautiful synchronized swimmer in an elaborate mermaid costume washes ashore dead, and the clues lead Jim to a bittersweet love triangle and a hip hop mogul trying to turn a mermaid show into multimillion-dollar phenomenon. On the home front, Callie hits a wall in her job search, and Jim realizes the best opportunity for her is the one in Atlanta she passed up to be with him.

Linden and Holder have the killer within reach. The Richmond campaign prepares for Election Day. The Larsen family attempts to regain a sense of normalcy.

Kyra and Carlos investigate a series of mysterious murders in which victims have been drained of endocrine fluid only to discover that the crimes were committed by Liber8 in an effort to save Travis, their leader. Kellog tries to make a truce with Kiera by delivering her a gift,one that could cost her and Carlos their lives and will lead to Kellog's expulsion from Liber8.

Alex drives on the Arctic Ocean, to the northernmost Canadian village accessible by ice road. Hugh and Rick face melting ice in a desperate search for missing trailers. In Alaska, a massive oil rig move continues as Jack struggles to mentor impatient young driver, Austin Wheeler. And, it's judgment day for the Dalton rookies as both Darrell and Porkchop meet with the boss to see if they pass their training runs.

Cathy tries scuba diving in an effort to maximize the fun on her Puerto Rico vacation; Paul, reeling from the news about Joy, tries to keep it together during a speaking engagement. Later, Sean decides to take a respite from dating after undergoing yet another breakup.

Roger seeks to expand his affair with Megan's mother. Pete has a "last" encounter with Beth with lasting repercussions. Megan struggles to find acting work and asks for Don's help getting an audition. Peggy still seeks Don's approval.

Alexander marks the Easter holiday with a glorious celebration and an end to his pious fast, while Della Rovere's assassin gets even closer to the pope. Meanwhile, Lucrezia's lover asks her father for her hand in marriage; and Juan's increasingly erratic behavior endangers his sister's child.

An Ohio gubernatorial candidate balks at Selina's endorsement due to her current unpopularity, but Mike and Amy try to make the best of the vice president's emotions during their meeting. Meanwhile, Dan can't shake the clean-jobs bill debacle, especially when it could be the subject of a Congressional hearing.

Riley gives romance a try with the very charming and ever persistent Dr. Mark. But what starts as an elegant date at a country club event, ends with her past coming back, turning Riley's world upside-down. Meanwhile, Dee Ann lands in hot water when she gets involved with a high-powered client. And Linette and Lacey face their first day of the "Reign of Taylor" at the Curl Up & Dry.

Longmire and his team investigate the death of an exotic dancer with possible Amish roots. Cady's new relationship stirs up controversy.

Hannah's lack of income forces her to take a job at Cafe Grumpy and her mood is not improved by discovering a former classmate has achieved literary success. Meanwhile, Jessa's former boss confronts her and Shoshanna starts internet dating.

Eric Andre and Hannibal Burress were joined by Joe Biden.

Toki goes to rock-and-roll camp and is bullied by other campers. But he soon finds an ally in a former Dethklok guitarist. Meanwhile, Skwisgaar and Murderface binge on candy and horror movies while Toki is away.

Greek salad is not as simple as it seems, particularly when it's been created by George! The three contestants in tonight's elimination challenge have three and a half hours to cook.

Finn is transported to the spirit world and needs the Ice King's help to escape; Finn and Jake attempt to rescue Marceline and find out what's making her behave so strangely.