Any “SNL” fan knows they have chemistry. They’ve shared the screen in sketches like “The Californians” or “Secret Word.” And we know they have the comedic chops: she’s Penelope and Dooneese and he’s, of course, Stefon. But as twins in a dramedy with a decently serious premise? Yeah, they kill that too.

The brilliant Kristen Wiig teams up with her former cast mate Bill Hader to headline “The Skeleton Twins,” a laugh-out-loud funny, tenderly bittersweet, often heartbreaking family drama. Hader plays Milo, who attempts suicide and subsequently repairs a long–estranged relationship with his equally depressed twin sister, Maggie (Wiig). Milo moves in with Maggie and her husband Lance (Luke Wilson, here nothing like his Emmett of “Legally Blonde”), who is incredibly earnest but has little in common with his wife’s gay brother. Sadness, sex and betrayal follow, but so does lip–syncing and a scene high on dental laughing gas.

You may have last seen Wiig on the big screen warning passengers about a colonial woman churning butter on the wing of the plane, but this is not “Bridesmaids” 2.0. Wiig has made onscreen strides into the dramatic since her Oscar–nominated hit, including her performances in “Friends With Kids,” “The Secret Life Of Walter Mitty” and “Girl Most Likely” (where Wiig is also a suicide–attempt survivor), but this latest offering is probably the most worth your time since her beloved tryst as Maya Rudolph’s maid of (dis)honor. She didn’t co–write, and there’s no wedding–dress–store–food–poisoning humor, but her charming onscreen interactions with Hader provide both laughs and tears.

“The Skeleton Twins” is not revolutionary—family dramas with heart and wit come around every once in a while—but it’s done right with the right balance of hilarity and heartache, which isn’t easy to master. In 93 minutes, you’ll grow to believe and feel for Maggie and Milo, largely thanks to the leads’ supremely silly and deeply grounded performances.

And for those of you who never knew you wanted to see Phil Dunphy go gay, you’re in for a treat: Ty Burrell of “Modern Family” is perfectly complicated as Milo’s much older ex–boyfriend.