The great writer, Terry Southern, once wrote, “You can’t do the end of the world in a conventionally dramatic way or boy meets girl way.” I guess writer Lorene Scafaria didn’t get the tweet.

Scene one: Dodge (Steve Carell) and his wife Linda (Nancy Carell … OMG, that’s Steve’s real wife) are sitting in their car on a dark road listening to the latest report on the soon-to-arrive 75-mile-long asteroid that is hurtling toward earth. Linda looks at Dodge. Her expression tells us that her marriage to this insurance salesman has been one long, emotional and spiritual colonoscopy, and that this is her chance to spend the last days of her life with someone who will wear a lampshade for a hat and dance naked with her. She gets out of the car and runs into the darkness. We never see her again. We won’t miss her.

Abandoned and confused, Dodge sinks into a stupor and starts drinking Windex and cough medicine with codeine. He wakes up one morning in a park with a cute dog on his chest. The note says “I’m sorry.”

Buckle up. Writer-director Scafaria, is taking us all on the last two weeks of the earth’s existence and we’re going to spend it with two wild crazy kids. Well, one wild crazy kid, an emotionally stunted dimwit named Penny (Keira Knightly) and the stunned and bewildered Dodge.

Penny and her brain-dead boyfriend have been living upstairs from Dodge and Linda for several years but have never met. Now, with doom on the doorstep, Penny leaves the boyfriend and stumbles into the dead calm of Dodge’s apartment with a month’s supply of his mail that has been delivered to her by mistake. Don’t ask.

Among the bills, there is a letter to Dodge from an old girlfriend who, seeing the end coming, confesses her life-long love for him.

As we might expect, Arab Spring-style riots are breaking out in the streets at night, with city-wide drunken revelry, fish fries, barbecues, lap dancing and hip-hop bacchanals. But being the practical folks they are, earthlings go back to work each day, paying their smart- phone bills and having their cars washed, as if the whole thing is just a “Saturday Night Live” joke. Hope springs eternal. Eventually, as the last working anchorman on the nightly news (Mark Moses) convinces all that the end really is at hand and walks away from the camera, the burning, looting and mayhem increase.

Now our voyagers take it on the lam across what appears to be New Jersey, to seek a reunion with Dodge’s lost love. They will share some freaky rides with freaky characters, including one trucker (William Petersen) who keeps his own burial tools in the back and suspects that Dodge is the assassin he hired to kill him.

Fatalistic, yet famished, our cute duo drop in at a diner called Friendsy’s (a combination of Burger King and Friendlys) where the locals and staff are having the last TGIF party of their lives, drinking up the profits and gorging on banana splits and heroin. This scene is the funniest one in the film.

Soon, writer/director Scafaria drops all attempts to make us laugh and turns to poignancy. Dodge’s lost love girl has apparently abandoned her Williams-Sonoma home and fled. But she has left lots of scented candles, wine and steaks for our hungry pilgrims. Here, some very long conversations will blend the two into one and give us each of their backstories before they move on to the last stop, Dodge’s childhood home.

Dodge’s estranged father will answer the door. It is a famous actor we’re not expecting, and I’ll leave the surprise for you as God knows you’ve needed one.

Will the end come? Will two damaged strangers find a moment of happiness on a soon-to-be-charred planet? Will the cute dog survive? Is that small aircraft in daddy’s back yard really the best deus ex machina Scafaria can come up with?

“Seeking” is not without laughs and a very funny Rob Corddry gives them to us, as he always does. But mostly “Seeking” comes up empty. Carell, who is a master at slapstick, seems lost without drunken buddies or the cast of “The Office.” Knightley has a few good moments in one scene. There is one beautiful moment that says so much about that wonderful force of denial we all embrace, when Dodge’s Mexican maid Elsa (a wonderful Tonita Castro) shows up to clean the house on the last day. “Elsa, why are you here?’ he asks. She shrugs and replies “It’s Tuesday.”

Happily, Julia Roberts does not make a cameo appearance, and no one gives away the secret to soylent green.

J.P. Devine is a former stage and screen actor.