It looks like the trigger/trigger guard assembly pivots as one unit, as the hand (which advances the cylinder) is attached at the rear of the trigger guard. At the same time the mainspring is compressed bringing the hammer back. Given the pivoting guard assembly, I'd say the actual trigger is the serrated part below and in front of the guard.
That makes perfect sense.
I just e-mailed my husband to tell him I want one and they're only five thousand bucks so we should get matching ones.
Dang, even a Glock is safer than that.