Am sitting watching pretending to watch Silent Witness with husband, the main character has said the above 3 times in this episode to various people.
Firstly, shouldn't it be may I have a word? Secondly, she should say "please". Thirdly, my experience has been that it's usually a bollockinglots of words as is the case in this show.
So if anyone says "Can I have a word?" to me, am gonna reply "No" instead of meekly stepping aside as seems to be required