On tonight's episode (May 31) of 'Duets,' the hilarious Robin Thicke and lovely Olivia Chisholm teamed up for 'Where Is the Love?,' a song Thicke said his wife, actress Paula Patton, sings around the house when they are play fighting. So the song has some personal meaning for him. It's also a much-loved, well-known and butter smooth duet.

During the rehearsals, Thicke was visibly miffed that Chisholm didn't memorize the lyrics as requested so she could focus on pitch and performance. He scolded her like any good mentor would and should, pointing out that he can screw up; she can't. It's the truth. He's established. She's in the "thicke" of competition and needs to do what her partner tells her. You hear that, 'Liv?

However, when they took the stage, Thicke turned on the blue-eyed soul charm, while Chisholm seemed to have gotten her act together. It was a smooth and beautiful rendition, and they had a sexy and sultry chemistry while performing. Chisholm's voice has a cool texture that we've not heard on any reality singing show in quite some time. There didn't seem to be any lyrical flubs, either.

We also appreciated how open and receptive Chisholm was to the constructive criticisms offered up by the celeb mentors.