What constitutes a "lying in wait" murder?

" 'Lying-in-wait murder consists of three elements: ' " '(1) a concealment of purpose, (2) a substantial period of watching and waiting for an opportune time to act, and (3) immediately thereafter, a surprise attack on an unsuspecting victim from a position of advantage . . . .' [Citations.]" ' " (People v. Russell (2010) 50 Cal.4th 1228, 1244, fn. omitted.) Lying in wait is " ' "the functional equivalent of proof of premeditation, deliberation and intent to kill." ' " (Id. at p. 1257.)