Shares of AMC Entertainment are diving by 25 percent Wednesday after the company revealed it expects a dramatic second-quarter loss, and believes the third quarter will be equally unrelenting.

AMC said the expected loss reflects "industry box office trends." American box offices declined 4.4 percent in the second-quarter compared with the same period last year, according to AMC.

Against this tide of declining moviegoing, the second-largest movie theater chain in the U.S. is attempting to curtail costs by cutting back on both its staff and operating hours, as well as through a new pricing strategy. But the cost reduction initiatives have yet to bear fruit this year.

"We were caught by surprise when AMC pre-announced second-quarter results over 30 days after the close of the quarter, and were further surprised by the magnitude of the top and bottom line miss," Wedbush Securities' Michael Pachter wrote in a note, along with a team of analysts.

AMC's adjusted projection for earnings before interest, taxes, depreciation and amortization "shocked" Pachter, who anticipated adjusted EBITDA of more than $200 million. Instead, AMC expects adjusted EBITDA to come in between $134 million and $136 million – or about $65 million short of Wedbush expectations.

With AMC's second-quarter report still to come, Pachter said "something doesn't sound right" before speculating that the company's expenses may be to blame.

"We can only surmise that the company had some unusual expenses during the quarter that it plans to eliminate in the next six months," Pachter said.

Wedbush is maintaining an outperform rating on AMC's stock, while the firm "anxiously awaits a more detailed explanation from management."

Eric Handler, media analyst at MKM Partners, told CNBC's "Power Lunch" on Wednesday that he does not see "a massive issue long term" for the movie theater chain and declared "the industry as a whole is healthy."

"People love to say the industry is dying if they have one or two bad quarters in a row. The year is still tracking flat, and when you look at the last two years, you've had record years," Handler said. "I think you're going to see another record year in 2018."

AMC's stock is down more than 53 percent this year, when it began near its 52-week high of $35.65. The company is expected to formally report second-quarter earnings Monday after the market close.

Correction: This story has been updated to reflect that it is solely about AMC Entertainment.