Finally 'off-the-shelf', virginal KITTY finds her bridegroom suffering a fatal heart attack when about to consummate the marriage. She then discovers that he's been two-timing her and embezzled her money. Traumatised, she takes to her bedroom, which best man ARCHIE can't coax her from. Gradually getting it together, Kitty traces NILS - a synesthete (a condition whereby emotions are seen tangibly, as colours). She decides to track Nils down and persuade him to 'discern' the man who truly loves her - her institution telling her he's amid her coterie of friends.
But Kitty discovers Nils to be a dandy, totally self-absorbed - who only goes with prostitutes because it's a monetary transaction, with no emotional attachment. Masquerading as a prostitute herself, to get closer to Nils, Kitty can't help but confess her dilemma just before coitus. But Nils's 'Technicolor brain' has had him discerning Kitty's subterfuge anyway. Kitty offers Nils money to discern the man who truly loves her for herself. At a 'commiseration' party for Kitty's 39th, Nils observes potential suitors flirting with her. He sees the perfect emotional colouration only around Archie, but keeps it to himself - to milk more payments. She accompanies him for test results, where it's announced that his abilities will suddenly dissipate to normal. Evidence comes to light that Archie was implicated in the late husband's shenanigans and he is arrested.
Nils uses his synesthetic abilities for a forensic investigation of Archie's profile, and convinces the police of the man's innocence. Meanwhile, Kitty goes to the deceased husband's grave, to try to intuit the truth there. The two men pick up on the 'emotional' residue of her footsteps. Nils gives the nod that Archie is the one for Kitty. Arm-in-arm, the new couple depart. Into Nils's line of vision (synesthesia now abated) comes the prostitute he regularly visited. He looks questioningly at her. Her smile broadens. Both couples walk off, arm in arm.