Newly elected to Congress, former local TV newsman Evan Baxter relocates from Buffalo with his family to suburban northern Virginia. His congressional campaign claims he will change the world, though he leaves the specifics ambiguous. On his inaugural day, he crosses paths with several coworkers including Marty (John Michael Higgins), Rita Daniels (Wanda Sykes), and top congressman Chuck Long. Shortly after settling in, bizarre occurrences begin to unfold:
1. Animals inexplicably follow Evan around.
2. He grows an unshavable beard that inexplicably regenerates.
3. Eight empty lots in the neighborhood are purchased under his name.
4. Mysterious ancient tools and wood are delivered to his home.
5. The number "614" surfaces everywhere he ventures.
Evan soon discovers this number refers to a passage in the book of Genesis, where God instructs Noah to construct an ark. Eventually, God appears and commands Evan to create a replica of Noah’s Ark to prepare for an impending flood. Initially, his family dismisses Evan's claims as an unusual mid-life crisis; however, as the situation escalates, his sons become intrigued and assist him in building the ark, while his wife Joan remains skeptical.
Later, God reveals to Evan that the flood is set to arrive at noon on September 22. As the madness continues, animals begin to follow Evan to Congress. When he attempts to explain the situation, mostly it results in him being suspended by Chuck Long. Shortly after, birds hilariously drop their waste on Chuck during Evan's departure, adding to the absurdity of the situation.
Distraught, Joan, thinking that abandoning Evan is the best choice for her and their three sons, takes them to her mother’s house. Meanwhile, Evan perseveres in building the ark solo, which garners significant media attention. In a surprising twist, God visits Joan at a diner disguised as a waiter named “Al Mighty,” and he imparts wisdom about the importance of family unity and opportunities. This realization leads Joan to return and support Evan in completing the ark.
As the fateful day approaches, it is revealed that Chuck Long, with shoddy designs, has commissioned a dam, further complicating matters. On September 22, as Evan prepares to load hundreds of animals onto the completed ark in front of a skeptical audience, initial signs of rain do not emerge, leading to criticism. Just as doubt begins to creep in, Joans urges Evan to abandon the ark. However, recalling the looming threat of the dam, he stays put—his instincts prove accurate as the dam bursts, inundating the streets of Washington D.C.
In a dramatic turn of events, with the streets flooded, citizens and police rush aboard the ark, which glides downstream, eventually docking at the Capitol. In the aftermath, Evan confronts Long, revealing that the flood was a direct result of his negligent dam design, leading to mounting opposition against him within Congress.
Later on a family hiking trip, Evan receives another visit from God, who emphasizes the importance of making a positive impact through Acts of Random Kindness ("ARK") as the pathway to transforming the world.
