India, Aug. 23 -- Paramount is giving fans a special surprise to help promote this week's digital release of Mission: Impossible - The Final Reckoning. But to fully enjoy it, you might need to know Morse code.

On Wednesday, the official X account for the Mission: Impossible series, led by Tom Cruise, posted a tempting offer. It sounded better than it really was. "The mission was compromised," the account said. "So we had one option left: release everything. Full movie on YouTube now." The post linked to a YouTube video from the Paramount Movies page.

When fans clicked the link, they didn't get the full movie. Instead, they saw a moving image that looked like an IMF spy radio sending a message. The video played an audio file with a long ...