AMC Entertainment Holdings (AMC -4.64%) is flying high these days. Even after taking a step back this week the leading multiplex operator is a 25-bagger in 2021. AMC's pop is even more stunning when you consider that the share count has climbed from 104.3 million at the end of June last year to more than 500 million today. We're talking about a 60-bagger over the past year in terms of market cap. 

With AMC generating so much attention, it's only natural to look for beneficiaries of the expanding valuations in the multiplex space. Regal Cinema parent Cineworld Group (CINE) (CNWGY)IMAX (IMAX 1.18%), and National CineMedia (NCMI -0.54%) seem like investments that could piggyback on the success of AMC. They may lack the fandom and short squeeze potential of the country's top movie theater chain, but it's fair to say that if the market thinks AMC is worth 60 times more what it was fetching a year ago, these three names have the potential to climb higher.

Theater patrons captivated at a movie theater and enjoying concessions.

Image source: Getty Images.

1. Cineworld Group 

Regal went from screen hero to villain last October, when it decided to shutter its theaters. Regal parent Cineworld joined AMC in reopening its locations earlier last summer as local ordinances allowed, but the lack of compelling theatrical releases proved financially draining. The last straw for Cineworld came when the latest film in the James Bond franchise, No Time to Die, pushed its big screen debut into 2021. 

Cineworld's decision to close all 543 of its U.S. Regal theaters along with its cinemas in the U.K. and Ireland helped spare the exhibitor from a dark stretch of operations, but it came at perhaps a greater cost. Regal has lost momentum with stateside viewers since reopening earlier this year. AMC's recovery has been smoother as it grabs early market share from its rival.

The appeal for Cineworld here is that in the same time AMC's market cap has exploded roughly 60-fold over the past year, we've seen Cineworld's market cap inch just 35% higher. AMC may be padding its market lead over Regal, but if Regal is 60 times the company it was a year ago, it follows to assume that Cineworld should at least be a double or triple in that time. 

2. IMAX

If you're going to catch F9 at an AMC near you this weekend, there's a good chance it's an IMAX screening. IMAX offers larger-than-life theatrical experiences, and it's a staple premium-priced offering at most AMC multiplexes. 

Unlike Regal, IMAX is an AMC partner. They both benefit financially when you're seeing a big action film on the enhanced IMAX projection platform. IMAX also has the benefit of its global reach. Movie theaters started bouncing back last year in many key overseas markets, putting IMAX ahead of the curve in the turnaround. 

IMAX revenue increased in its latest quarter, climbing 11% through the first three months of this year.  AMC's year-over-year revenue plummeted 84% in the same quarter. 

3. National CineMedia

The smallest -- and riskiest -- of the three coattail plays here is National CineMedia, a provider of in-theater advertising. Yes, National CineMedia is the company you can blame for the long roll of ads before even the trailers start at your local movie house. Exhibitors turn to the turnkey solution to monetize their traffic through the on-screen advertising network.

B. Riley analyst Eric Wold bumped his price target on National CineMedia higher on Thursday, from $6 to $7, on the potential of a rebound. He sees in-theater advertising taking a larger chunk of marketing budgets with stronger pricing as advertisers pay up to reach younger audiences that aren't easy to grab these days. 

National CineMedia was consistently profitable until last year. Annual revenue has been stuck at around $445 million for the past few years before last year's plunge, but National CineMedia current market cap of $405 million is less than that -- and the stock is fetching less than 11 times its 2019 earnings. 

AMC's value as a media stock is soaring heading into an industry recovery. If that's the case then one can reasonably expect Cineworld, IMAX, and National CineMedia to also cash in on the upbeat Hollywood ending.