McKellen, 75, is Freddie Thornhill, an actor whose intense narcissism compensates for a lackluster career. Jacobi, also 75, plays Stuart Bixby, a one-time bartender and would-be model who has ridden Freddie's coattails.
The couple's intense youthful passion has transformed after half a century into a passion for bickering. That, essentially, is the show in a nutshell: the actors lobbing a series of put-downs, zingers, accusations, and insults - always liberally peppered with sexual innuendos - at each other.
The show's only other regulars, longtime friend Violet (Frances de la Tour) and a young hot neighbor named Ash (Iwan Rheon), drop in from time to time to referee.
Vicious is Two and a Half Men for pensioners. Some of the jokes admittedly are very funny, but they are ruined by a hideous laugh track. Why on earth would these two actors stand for a laugh track? A mystery for the ages.
Morse, the younger
Shaun Evans continues his remarkable performance as young police detective Endeavour Morse in a second outing of Masterpiece Mystery!'s thoroughly absorbing Endeavour, which premieres at 9 p.m. with the first of four feature-length mysteries.
Set in the mid-1960s, Endeavour is a prequel of sorts to Inspector Morse, a widely beloved adaptation of author Colin Dexter's novels that starred John Thaw as a brooding, middle-aged police detective. An almost fanatical devotee of opera and classical music, the middle-aged Morse was a brilliant thinker who never finished his Oxford education. A brooder, he was wary of women and endlessly fascinated by them - his heart had yet to mend from an intense love affair during college. Endeavour shows us how he became a great detective and a thoroughly lovable if deeply damaged man.
'Last Tango' redux
Last season, Last Tango in Halifax made for a delightful addition to the TV roster with its fresh, touching storyline about a widowed man and woman in their 70s who pursue a romance despite the disapproval of their children and grandchildren.
The story ended with a cliffhanger: Alan (Jacobi) and Celia (Anne Reid) had a fight, but before they could make up, Alan had a heart attack.
Jacobi and Reid are brilliant, but the show, which premieres at 8 p.m., has lost its novelty. One wonders why the series needs to continue beyond the inevitable reconciliation and wedding - which come early in the season opener.
Last Tango in Halifax
8 p.m. Sunday on WHYY TV12
Masterpiece Mystery!: Endeavour
9 p.m. Sunday on WHYY TV12
10:30 p.m. Sunday on WHYY TV12