Neil Simon, one of the great American comic playwrights. Vaudeville comedy. Danny DeVito and Judd Hirsch, "Taxi" costars, reunited once again. Given these elements, "The Sunshine Boys," now playing at the Ahmanson, should be a laugh riot. Unfortunately, that's not quite the case.

The play opens on Willie Clark (DeVito, "It's Always Sunny in Philadelphia"), an aging comedian who can't remember his own family's name, but who has a stellar memory for everything he detests about his former performing partner, Al Lewis (Hirsch). Since Clark cannot even recall the name of the product he is supposed to sell when he films a commercial, his nephew/agent, Ben (Justin Bartha) has been having difficulty finding him work. However, a glimmer of hope arrives in the form of a CBS retrospective on comedy. Suddenly, the vaudeville duo of Lewis and Clark, the Sunshine Boys, is in demand again—though their success depends on whether or not Lewis and Clark can get along for long enough to reenact their most famous sketch.

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Simon's script is, at this point, a period piece, and that proves to be part of the problem. The piece's racist and sexist jokes don't sit well, and that discomfort casts a weird shadow over the play as a whole. Another issue lies in the fact that the play seems to find itself funnier than it actually is. While the script and actors churn out funny moments fairly regularly, after a while, the laughter starts to feel more obligated than organically inspired. Like its characters, "The Sunshine Boys" wears out its welcome fairly quickly, and ceases to be likable.

There's nothing specifically bad about "The Sunshine Boys." Under director Thea Sharrock, all of the individual parts are fine. Particular standouts are Cricket S. Myers' sound design, which works nicely in the Ahmanson, and Bartha ("The Hangover" movies, "Asuncion"), who plays the part of the straight man adeptly and charmingly. The individual parts just don't work together to create an impressive final product.

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What is most perplexing about "The Sunshine Boys" is the lack of chemistry between DeVito and Hirsch. For all that this production is being touted as a reunion of the two actors, who starred together in "Taxi" for five years in the late 70s to early 80s, there is no sense of history between the two beyond what is explicitly stated in the script. Given their history with each other, it's hard not to expect a tantalizing electricity between the two actors, or for their gags to bounce off each other effortlessly. Neither is the case, though, and their relationship fizzles on stage alongside the jokes that don't quite land.

"The Sunshine Boys" is not a bad show. It has its moments, and it is mildly funny. Given the outstanding elements going into the show, though, it's hard not to be disappointed that the whole is considerably less than the sum of its parts.

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"The Sunshine Boys," plays through November 3 at the Ahmanson Theatre (135 N. Grand Ave, Los Angeles). Tickets are $20-$115. More information can be found at CenterTheatreGroup.org.