Something’s sorely missing in this dictionary definition of the word “righteous,” described as: “acting in accord with divine or moral law; free from guilt or sin.” Fine and good, but what about “musically slammin’” and “nostalgically heartwarming”?

You don’t invoke that word without pairing it with “Brothers.” Not if you’re an aficionado of those last two definitions, both of which are reinforced at the new Righteous Brothers residency. Original bro Bill Medley revives the iconic act with Branson veteran Bucky Heard stepping in for the late Bobby Hatfield, who died in 2003 (and receives a video tribute in the show as Medley sings a solo version of “Unchained Melody.”). Accompanied by an eight-piece band and three female backup singers, Medley’s rich bass-baritone blends with Heard’s tenor vocalizations in Hatfield’s style to refresh the “blue-eyed soul” that made stars of Medley and Hatfield, whose classics—recorded between 1963 and 1975—are revisited here. And in a rebuke to the aging process, Medley’s deep, emotive vocals, even at age 75, still sound like they were newly excavated from a gold mine.

In a show goosed by Medley’s impish one-liners, the duo also fit together in a kind of father/son vibe—the source of much of Medley’s good-natured wisecracks—and hit all the highlights from a storied career. Revel in the memories when they launch into “Turn On Your Love Light,” “Little Latin Lupe Lu,” “Soul & Inspiration” and “Koko Joe.” Other highlights include Heard’s solo moments—closely echoing Hatfield’s memorable recording and goose-bump-inducing falsetto on the lush, romantic “Ebb Tide” and tackling Roy Orbison’s octave-jumping “Crying”; Medley’s duet with his surprise guest, his daughter, McKenna, replacing Jennifer Warnes on “(I’ve Had) The Time of My Life”; and the guys’ stellar “We Gotta Get Out of This Place,” “Rock and Roll Heaven” and “You’ll Never Walk Alone.”

Climaxing this nostalgia fest is, of course, “You’ve Lost That Lovin’ Feeling.”

Lovin’ feeling … found.

Harrah’s, 6 p.m. Wed.-Fri., 7:30 p.m. Sat., $39-$125 plus tax and fee. 702.777.2782