The stepson of British billionaire Hamish Harding believes Blink-182 will get him through "life's toughest times."

Brian Szasz spoke out on social media to defend his decision to attend a Blink-182 concert amid a high-stakes rescue mission to find his stepfather, as well as four other passengers, onboard the missing Titanic submersible.

"Yes I went to @blink-182 last night," Szasz, an audio engineer based in San Diego, wrote on his Instagram Stories June 20 alongside a photo of him at the venue. "What am I supposed to do sit at home and watch the news? Not sorry this band has helped me through hard times since 1998."

The 37-year-old shared news of his outing on Facebook June 19, according to screenshots obtained by multiple outlets, where he wrote, "It might be distasteful being here but my family would want me to be at the blink-182 show as it's my favorite band and music helps me in difficult times!"

He later deleted the post, noting that his mom Linda "asked me to delete all related posts. Thanks for the support."

Meanwhile, on Twitter, Szasz expressed his gratitude to Blink-182 band members Tom DeLonge, Travis Barker and Mark Hoppus.

"My stepdad Hamish is on this submarine lost at sea," Szasz tweeted. "I'm devastated but coming to the San Diego show tonight so you guys can give me hope and cheer me up."

The 21-foot submersible—named Titan—lost contact with Canadian Research Vessel Polar Prince on June 18 approximately an hour and 45 minutes into its dive to view the wreckage of the RMS Titanic, according to the United States Coast Guard News.

Titan was part of an OceanGate Expeditions tour—which explores the RMC Titanic, the ship that sank in 1912 and inspired James Cameron's Titanic—and is located about approximately 900 nautical miles East of Cape Cod, according to the Coast Guard.

"Our entire focus is on the crew members in the submersible and their families," OceanGate said in a statement, obtained by NBC News, "we are deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to reestablish contact with the submersible."

Along with Harding, CEO Stockton Rush, French explorer Paul-Henri Nargeolet, Pakistani businessman Shahzada Dawood and his 19-year-old son Suleman Dawood are on board.

Keep scrolling to learn more about the five-member crew onboard the Titan submersible...

On June 18, 2023, a deep-sea submersible Titan, operated by the U.S.-based company OceanGate Expeditions and carrying five people on a voyage to the wreck of the Titanic, was declared missing. Following a five-day search, the U.S. Coast Guard announced at a June 22 press conference that the vessel suffered a "catastrophic implosion" that killed all five passengers on board.

Pakistani-born businessman Shahzada Dawood and his 19-year-old son Suleman Dawood, both British citizens, were also among the victims.

Their family is one of the wealthiest in Pakistan, with Shahzada Dawood serving as the vice chairman of Engro Corporation, per The New York Times. His son was studying at the University of Strathclyde in Glasgow, Scotland.

Shahzada's sister Azmeh Dawood told NBC News that Suleman had expressed reluctance about going on the voyage, informing a relative that he "wasn't very up for it" and felt "terrified" about the trip to explore the wreckage of the Titanic, but ultimately went to please his father, a Titanic fan, for Father's Day.

The Dawood Foundation mourned their deaths in a statement to the website, saying, "It is with profound grief that we announce the passing of Shahzada and Suleman Dawood. Our beloved sons were aboard OceanGagte's Titan submersible that perished underwater. Please continue to keep the departed souls and our family in your prayers during this difficult period of mourning."

OceanGate CEO Stockton Rush was the pilot of the Titan. The entrepreneur—who founded the research company in 2009 in Everett, Wash.—had long been interested in exploration. Rush, 61, previously said he dreamed of becoming the first person on Mars and once said that he'd "like to be remembered as an innovator."

In addition to leading voyages to see the remnants of the Titanic, Rush had another surprising connection to the historic 1912 event: His wife Wendy Rush is the great-great-granddaughter of a couple who died on the Titanic, Ida and Isidor Straus.

British billionaire Hamish Harding confirmed he was a part of the mission in a June 17 Instagram post, a day before the submersible went into the water and disappeared.

"I am proud to finally announce that I joined @oceangateexped for their RMS TITANIC Mission as a mission specialist on the sub going down to the Titanic," he wrote. "Due to the worst winter in Newfoundland in 40 years, this mission is likely to be the first and only manned mission to the Titanic in 2023. A weather window has just opened up and we are going to attempt a dive tomorrow."

Harding—the chairman of aircraft company Action Aviation—said the group had started steaming from St. Johns, Newfoundland, Canada and was planning to start dive operations around 4 a.m. on June 18. The 58-year-old added, "Until then we have a lot of preparations and briefings to do."

His past explorations included traveling to the deepest part of the ocean in the Mariana Trench, telling Gulf News in 2021, "It was an incredibly hostile environment. To travel to parts of the Challenger Deep where no human had ever been before was truly remarkable."

The Dubai-based businessman also circumnavigated the Earth by plane with the One More Orbit project and, last year, took a trip to space on Amazon founder Jeff Bezos' Blue Origin New Shepard rocket. Harding shared his love for adventure with his son Giles, described as a "teen explorer" on his Instagram.

As for the fifth member, a representative for French explorer Paul-Henri Nargeolet told the New York Times that he was a passenger on the Titan, with Harding also referencing him on Instagram as a member of the team. 

The Times described him as a maritime expert who was previously part of the French Navy. The 71-year-old was a bonafide Titanic specialist and has traveled to the wreckage 35 times before. Nargeolet served as the director of RMS Titanic, Inc., a company that researches, salvages and displays artifacts from the famed ship, per the outlet. 

Alongside fellow passenger Hamish Harding, he was a member of The Explorers Club, founded in 1904.

As Harding noted in his post, the submersible—named Titan—was a part of an OceanGate Expeditions tour that explores the wreckage of the RMS Titanic, which infamously sank in 1912.

The company expressed its sympathies to the families of the victims. "These men were true explorers who shared a distinct spirit of adventure, and a deep passion for exploring and protecting the world's oceans," OceanGate said in a statement. "Our hearts are with these five souls and every member of their families during this tragic time. We grieve the loss of life and joy they brought to everyone they knew."

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