During the wee hours of the night, a small line of people started forming outside the Washington Convention Center this past Thursday. By mid-morning on Friday, it extended all the way around the northwest corner of the building.

It was no concert ticket sale or grand opening of a new store. It was a hoard of entrepreneurs, all of them hoping to be thrown into the “Shark Tank.”

Hundreds of individuals, business partners and entire families traveled from around the country to show their latest inventions and fledgling start-ups to the casting directors for ABC’s reality show, in which aspiring entrepreneurs pitch their ideas to a panel of celebrity investors.

(Photos by J.D. Harrison / The Washington Post/Photos edited using Instagram)

It was the last of seven casting calls for the show’s fifth season and the first step in what one producer called “a long, long road” for those who want to pitch their start-ups to the likes of Dallas Mavericks owner Mark Cuban, FUBU founder Daymond John and Paul Mitchell founder John Paul Dejoria — all in front on several million television viewers.

On Small Business caught up with dozens of them during the day. We were invited to eavesdrop on some of the pitch performances. Here’s a look at a few of the entrepreneurs we met and their unique start-up ideas.

Matt Murphy, Knockey

Murphy flew down from Boston to demo Knockey, a device that allows users to unlock any door using the sound of a preset knock pattern. Murphy works in real estate and got tired of being locked out of properties when keys didn’t function.

ToniAnn Galati, Couture Wedding and Sweet Sixteen Dresses

Galati drove down with her husband from New Jersey to show off her design for a mix-and-match dress, parts of which can be added and removed to transform the garment into various shapes and designs. Galati’s entire inventory was destroyed when Hurricane Sandy slammed her home last year, and the displays she brought to Washington were sewn out of donated curtains.

“We basically had to piece this all together using random scraps of fabric,” Galati said after her pitch.

Keela Castle, Castle Crowns

Combining real human hair with scares and headwraps, Castle says her products serve as a simpler and more affordable alternative to a full wig. Castle flew from Marina Del Rey, Calif. to pitch them to the “Shark Tank” casting team.

Philip Morrow, Hocoo Comfort Tie

Morrow traveled from the Bronx in New York to pitch his Hocoo Comfort Tie, which contains a heating strip behind the neck as well as a tiny phone-charging station embedded in the necktie.

“I think it went well, they really liked the idea of the neckwarmer inside the tie,” Morrow said afterward.

Tselane Robertson, Tlane6, Inc.

Robertson (left) developed a pepper spray that, when activated, also starts recording video, helping victims of attacks later identify their assailants. Based in Herndon, Va., she started working on the project after her sister (right) was the victim of a violent assault, and the attacker was never apprehended.

Frank Gilmartin, Bite N Lite

Based in Bel Air, Md., Gilmartin (right) and his brother pitched Bite-N-Line, an electronic lighting system that allows fishermen to monitor their lines in the water at night. Once a fish nabs the bait, the light flashes as it gets pulled under the water.

“Right now, most folks just wrap their line around a glow stick, but those burn out pretty quick,” Gilmartin said.

Willie Johnson, Point MMA

Johnson has been running his mixed martial arts program for years in Laurel, Md., and he came to “Shark Tank” in an effort to expand the company’s reach nationwide. One of the program’s primary goals is to get children and families involved in mixed martial arts.

Kevin Bunn, Sockdock

Bunn drove four hours from North Carolina (with his seven-year-old son and three-month-old daughter in tow) to show investors the Sockdock, which clamps matching pairs together in the washing machine and dryer.

“Next time, we have to find a nanny,” Bunn said after the pitch, noting that he had to keep an eye on the children during his presentation.

So, what’s next for these entrepreneurs?

If any of them make it through to the next round, they will be asked to produce a short video segment to send to the casting directors, explaining their product and their business plan in more detail. If their idea continues to impress, they will be asked to fly out to the show’s studio in California for several more rounds of preliminary cuts.

Only a select few actually get thrown in front of the sharks.

Which idea do you think has the most promise? Would you invest in any of these startups?

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