In Criminal Minds, its usually about 6 of them in a row, doing what you describe.In American cop shows in particular:
There’s a briefing (often in front of some incredibly high tech PowerPoint screen) and one Detective/FBI agent starts the briefing.
There’s never any fumbling or ‘where’s the full screen button’. They never go backwards in the presentation by mistake. There’s never a duff graphic.
Then, at some random point, mid-paragraph, the first presenter will have over to the next one: well not really a handover- the first one takes a breath and then the second presenter takes over without a second’s pause.