If you admire Neil Simon’s work, be sure to take in the spirited revival of his 1972 play The Sunshine Boys, now running at Bristol Riverside Theatre. It is theater within theater, as television folks try to entice the Sunshine Boys – the old vaudeville team of Lewis & Clark – to do a cameo for a show on the history of comedy.

Reminiscent of Simon’s salad days with Sid Caesar, Sunshine sizzles with odd situations and zingers. It’s mainly a two-man dust-up: Think The Odd Couple. Willie Clark nurses an old grudge toward sidekick Al Lewis, who retired 11 years ago and scuttled their act.

Willie is a comical curmudgeon who lives in the past, consumed with petty anger, too prideful to recognize his small place in a changing world. Here is the good news: There is no schmaltzy kiss-and-make-up, because Willie stays in character right up to the ironic, “happy” ending.

Carl Wallnau makes you feel the depth of Willie’s dissemblance. Willie likes to think he is out in the world, but Wallnau’s pinched, routinized movement captures his shut-in reality. Only the arrival of Al brings him back to life, and the apartment then becomes a stage for a real-life vaudeville show.

Allen Lewis Rickman plays Willie’s old sidekick with rib-tickling blandness. Willie sizes up Al like a stalking animal. Wallnau’s delivery of Yiddish-inflected barbs is impeccable, but Willie grows still more furious once he sees that happily retired Al cannot grasp his anger.

Willie can only ignore the others around him. The TV execs are dismissive. Nicole Benoit gives him a rise as the sexpot, stage-prop nurse, but Willie’s real personal nurse (Demetria Joyce Bailey) dishes out a sassy reality check. And throughout, caring nephew Ben (Jason Silverman) tiptoes around, gently trying to tell Willie his vaudeville world is bye-bye.

But Willie will not take it in. Director Keith Baker skillfully fluffs the pillows for a play that is, in spirit, a twofer. Cleverly, Jason Simms’ apartment design looks elegant in semi-darkness. But you gasp at its shabbiness when the lights go on. Linda B. Stockton exposes true character with telltale costumes.

Perhaps stung by critics who called him a lightweight, Simon made a midlife course correction. Beginning with I Ought to Be in Pictures (1980), he drew on his own suffering to write more somberly, stretching genres of comedy and tragedy with Shakespearean restlessness. His “serious” works rightfully won acclaim, but they do not top the electricity, verve, and pathos of his earlier “entertainments.” The handsomely mounted show at Bristol Riverside suggests The Sunshine Boys is among his best.

THEATER REVIEW

The Sunshine Boys

Through March 31 at Bristol Riverside Theatre, 120 S. Radcliffe St., Bristol. Tickets: $35-$50. Information: 215-785-0100, brtstage.org.