Not actually dead, recipient's UI system will crash, he will see a black screen for a while. After that, message app will be not working anymore.
This is working not only with an SMS, but with other applications that can send push notifications. There is a defect in some UI elements in iOS which cause this crash if they want to display one latin, two Arabic, two Marathi and one Chinese symbol at the same time.
Here is original text of the "Unicode of Death" SMS:
Power لُلُصّبُلُلصّبُررً ॣ ॣh ॣ ॣ 冗
But minimum required text is here (one latin, two Arabic, two Marathi and one Chinese symbol):
а رر ॣ ॣ 冗
DO NOT SEND THIS MESSAGE!
But if you did that or someone sent it to you, your message application is broken now.
To recover your message app you need to do the following:
- Enable Siri (go to Settings -> General -> Siri)
- Hold home button to start Siri
- Say "read unread messages"
- When Siri asks you to reply to the message, say "Yes"
- Now you can open your message app
- Swipe left to delete whole thread with the malicious message.
- Or tap and hold malicious message then tap More and Delete\
Now you can use messages again. Apple will fix this bug in the next update.