What's got(ten) into (someone)?

What's got(ten) into (someone)?

Why is someone acting in such an unusual or unpleasant way? What is upsetting or bothering someone? Jeff just screamed at me and stormed out of the room. What's gotten into him? What's got into Sarah? She's been avoiding me for days now. I don't know what has gotten into him lately. He just isn't acting like himself.
Farlex Dictionary of Idioms.

What's got(ten) into someone?

What is bothering someone?; What caused someone to act that way? (Past or perfect only. The has is contracted except for emphasis.) I just don't know what's gotten into her. I don't know what got into me.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

what’s got into somebody?

(spoken) used to say that somebody has suddenly started to behave in a strange or different way: What’s got into Alex? He never used to worry like that.
Farlex Partner Idioms Dictionary
See also:
  • accompany (one) on a/(one's) journey
  • accompany on a journey
  • a stranger to (someone or something)
  • be out of (one's) league
  • be out of somebody's league
  • be in bad with (someone)
  • (one) puts (one's) pants on one leg at a time
  • bargain
  • bargain for (someone or something) with (someone)
  • brief (someone) about (someone or something)