The fortunes of Netflix are booming.
Subscriber numbers are up.
They've just announced a price bump, so investors are happy.
And big budget productions like Bird Box are racking up millions of views a day.
But there's one surprising thing that's got CEO Reed Hastings worried.
It's not HBO or Hulu - it's video game 'Fortnite'.
Nearly 80 million people played the smash hit in August alone.
And it's numbers like that, that mean the battle royale may have cashed in over 2.4 billion in sales last year.
That's more than any Hollywood blockbuster released in 2018.
And it's caused the Netflix chief to send a letter shareholders saying he sees Fortnite as a major competitor.
Reuters Breakingviews columnist Robyn Mak explains why.
(SOUNDBITE) (English) REUTERS BREAKINGVIEWS COLUMNIST ROBYN MAK, SAYING: "That's really odd if you think about it because Fortnite is a game - but if you look closely, then you can sort of see why these traditional media companies will be concerned.
Each game is quite simple and addictive, it lasts you know 10-15 minutes, and it's incredibly popular among young and old people." That simplicity means it's not just fun to play, but it's also fun to watch.
(SOUNDBITE) (English) REUTERS BREAKINGVIEWS COLUMNIST ROBYN MAK, SAYING: "But also lots of people really enjoy just watching other people play this game.
So on video sites like twitch lots of people log in to stream other people play Fortnite as well.
And that's really eating into the time that people would normally spend on other platforms and sites." And that's gained it a global audience of more than 200 million players.
And all those eyes watching and playing 'Fortnite'?
That's potentially a very big hole in the Netflix audience.
(SOUNDBITE) (English) REUTERS BREAKINGVIEWS COLUMNIST ROBYN MAK, SAYING: "If lots of people are spending their time on Fortnite, watching Fortnite, then they're spending less time on Netflix or Disney or HBO." So for now, it looks like the giants of content may be right to be alarmed by the meteoric rise of 'Fortnite' and the massive audiences games like it pull down online.