The time: not that far in the future, by some accounts, by others Right Now.  The place: a world not much unlike Earth in all the ways that matter (although okay, the sky's yellow more than it's not and the clouds are a little thicker but they addressed that, really they did, and it won't kill you unless you stand out in it all day.  Probably).  The cast: the usual suspects.

There's something to be said for dropping in unannounced.  Admittedly, it tends to be the Doctor's main method for visiting, but it has a fair amount of appeal all the same; if who you're visiting can't predict your arrival, they can't intentionally avoid being there in the first place.  You either expect a visit every day or settle into the complacency of "not today," and that, in all honesty, is where the Doctor likes them.  So many more interesting things happen when people aren't expecting you, when they assume tomorrow is the day when it will happen instead of today.  It gives you much better insight into people, he's found.

Today is no different.  The telltale whirr and the TARDIS arrives within walking distance of wherever a certain captain has made himself at home for the moment, and not long after Doctor and Companion step out onto the street.