be up to (one's) neck in (something)
be up to (one's) neck in (something)
be up to your ˈneck in something
,be in something up to your ˈneck
1 have a lot of something to deal with: I’ve been up to my neck in job applications for weeks.
2 be deeply involved in something, especially something dangerous or criminal: He says he knows nothing about the drug smuggling, but the police are sure he’s in it (= trouble) up to his neck.