MADRID — Following up her Emmy for “Game Change,” Julianne Moore has booked a seat on “Non Stop,” a movie that reteams “Unknown’s” Liam Neeson, helmer Jaume Collet-Serra, Joel Silver and Studiocanal.Michelle Dockery (“Downton Abbey”) and Scoot McNairy (“Argo”) have also joined key cast of the air-flight action-thriller that is budgeted at about $50 million, according to Studiocanal chairman-CEO Olivier Courson. With Neeson fresh off a chart-topping first-frame $105 million at the U.S. box office for another action-thriller, “Taken 2,” “Non Stop” looks like one of the weightiest of new productions that will be sold at the American Film Market. In Neeson’s next acting gig after “Taken 2,” he plays a federal air marshal who starts receiving text messages from someone claiming to be on the same flight, and who is threatening to kill its passengers. Racing against the clock, Neeson’s character must identify and stop the killer. “Non-Stop” initiates principal photography Nov. 1 in New York. Collet-Serra directs from a screenplay by John Richardson and Chris Roach. Silver, Andrew Rona and Alex Heineman produce. Studiocanal is fully financing the action-thriller, owns world rights and will distribute directly in U.K., France, Germany, Australia and New Zealand. Studiocanal will also handle sales for the rest of the world. For the U.S., “Non Stop” will be a major studio release, Courson said. “Non Stop” is the biggest-budgeted film Studiocanal has ever fully financed, alongside “Paddington.” “After ‘Taken 2,’ ‘Non Stop’ will be a big catch for any studio,” Courson added. Dockery (“Hanna”) broke through playing Lady Mary Crawley in “Downton Abbey.” Named as one of Variety’s 10 Actors to Watch in 2012, McNairy came to attention at Cannes in The Weinstein Co.’s “Killing Them Softly.” Casting of another Variety Actor to Watch, Nate Parker (“Arbitrage”), was announced Friday. Moore is repped by CAA’s Kevin Huvane, Dockery by Christian Hodell at Hamilton Hodell, and McNairy by ICM Partners’ Nigel Meiojas. Elsa Keslassy contributed to this report.