Nobody likes a grass. Except on screen, where a snitch has proved a powerful protagonist in some of the most memorable gangster thrillers over the last three decades.
'Black Mass', out this week in cinemas, provides a worthy addition to that roll-call, with Johnny Depp unrecognisable as Jimmy 'Whitey' Bulger', a gangster among the deadliest of Boston's 1970s kingpins, turned one of the FBI's most notorious informants.
What do we know about snitches? That they rarely emerge unscathed. As you can see from our list of the best below, the saying 'snitches' get snitches' is not without foundation... what's your favourite of this lot?
'Black Mass' is in UK cinemas from Wednesday 25 November.