"That's it, keep him talking," the Doctor muttered, crossing
some more wires.
        "I'll give him this, that's never been difficult," Don said from
the depths of his matching efforts on the other side of the room.  The
Doctor glanced briefly over his shoulder at his young colleague - it was
a good sign that Don could find it in himself to quip at a time like
this - and they shared a brief grin before getting back to work.
        "This is brilliant," he said, half to himself.
        "Just like old times," Don agreed.
        "Better.  You got older and I got younger."  The Doctor glanced
over his shoulder again, then went back to it.  "I think we're about the
same relative age now.  Makes all the difference."