What is the usage of "is that a start?" here?
This is a dialog between off-duty SP with a terrorist bomber from the TV-show "Bodyguard".
After "Does it sound OK to you?" he adds "Just talk, is that a start?"
- You don't look like you do (will push the button).
Listen, the specialist counter-terrorism unit already know about a potential incident on this train.
So what I'd like to do is just tell them that you're willing to talk.
Does that sound OK to you? Just talk, is that a start?
(Talking to the train-guide )
- There's a second bomber but we're talking.
Now write this down "Young Asian female, equipped with an explosives vest. Advise SCO19 she's willing to talk."