When Whitney disagrees with Mark's theory that couples know if they want to be together within 48 hours of meeting, Alex tries to prove her wrong by recalling the night they met.

Trying out a new shapelier bra Whitney gets more than she bargains for when she entices Alex with her enhanced look. After Roxanne calls it quits with Lance, she asks Mark to help pack up his stuff, but things become complicated when Mark decides to take advantage of the situation. Meanwhile, Lily and Neal begin discussing a pre-nup, but the conversation leaves them wondering if they should even get married.

Whitney confronts Alex after finding a box of his ex-girlfriend's stuff in the basement; Lily tries to be a perfect roommate.

Whitney is stunned when she discovers Roxanne's ex-husband is back in town; Neal is unsure of what to do when faced with racisim; Lily loses her engagement ring.

Alex drunkenly proposes to Whitney after a bachelor party. Mark realizes he has feelings for Roxanne.

Whitney decides to investigate when she sees her psychiatrist eating a birthday cake by herself; Roxanne admits her feelings for Mark.

Whitney and Lily have a disagreement over the wedding plans; Alex asks Neal to help him pitch his website idea; Roxanne and Mark donate blood.

Whitney has an unexpected reaction when confronted with a mugger; Lily tries to keep herself busy after her and Neal's wedding is called off; Mark encourages Neal to talk about his feelings.

When Whitney is hard up for cash, she and Alex decide to share a joint checking account; Mark buys a bar.

Whitney is upset when Alex won't give her the password to his phone; Whitney finds Alex in an awkward position; Lily has jitters about her new living arrangement.

In an effort to help Whitney earn some money, Roxanne hires her to be her assistant and office spy. Willing to do anything to help Roxanne, Whitney befriends Lindsay (Kathy Griffin), the assistant to Roxanne's nemesis, and goes out of her way to appeal to her. Meanwhile, alone at home Alex takes it upon himself to do a little reorganizing. Elsewhere, Mark, who is dealing with a girl problem, enlists the help of Neal and Lily.

Whitney and Alex make a surprise visit to Neal's apartment and discover that he appears to be on a date. Whitney invites the gang to dinner so Neal can share his news with Lily.

Whitney blurts out her true feelings to Alex's abrasive brother; Lily plans a secret date for Mark and Roxanne.

When Alex becomes jealous of one of Whitney's co-workers, the two decide to try couples therapy; Mark and Roxanne realize they make good partners while at Lily and Neal's game night.

While trying to figure out what is making Alex's allergies act up, Whitney reveals she has a heart condition; Lily introduces her new boyfriend to her friends.

After an argument over whether or not Alex uses a condescending "tone," Whitney decides she is going to catch her boyfriend in the act and enlists Mark's help. The two scheme to set up a hidden camera in the couple's apartment. Lily, Roxanne and Neal gather around the television to watch the drama unfold. Later, Alex's brother Brian crashes on the couch, and old sibling rivalries come to the surface causing the two brothers to brawl.

Whitney and Alex head to City Hall to get married, but Whitney's driver's license is expired and sparks an unusual chain of events that interferes with their wedding plan. Whitney's father tries to come to the rescue. Mark confesses his feelings for Roxanne to Neal and Lily.

Whitney's mother interrupts the celebratory mood of Whitney and Alex's unofficial wedding day; Lily and Roxanne have trouble choosing a gift for Whitney.

Whitney's half-sister visits to discuss a life-altering decision; Alex and Mark try to cheer a depressed R.J.

When Alex (Chris D'Elia) encourages Mark (Dan O'Brien) to recycle his beer can, Mark takes an unusually firm stance against it, causing the two to "break-up." Trying to cheer Alex up, Whitney (Whitney Cummings) steps in for guy's night out, only to run into Mark and his new best friend, Neal (Maulik Pancholy). In an effort to reunite the bro-mance, Whitney, following advice from Lily (Zoe Lister-Jones) and Roxanne (Rhea Seehorn), arms herself with some Rocky Road and red wine and sets out to discover the real root of Mark's heartbreak.

Whitney and Alex scheme a way to skip out on their family gatherings to start new holiday traditions with their friends Lily, Neal, Mark and Roxanne. However, Whitney's little white lie to her mother Candi and an unexpected visit from her father, Vince, cause her perfect plan of merriment to unravel.

Whitney's reaction is less than heartwarming when Alex falls off a stage while speaking at his alma mater; R.J. tries to teach Mark about chivalry.

A terrible ex-boyfriend contacts Whitney in hope of making amends; R.J. presents a theory to Roxanne.

Whitney thinks her father has changed for the better when he visits and gives her $5,000; while Alex thinks Whitney should rent an art gallery and display her photos, Whitney gives the money to Lily, who is very short on cash.

Whitney asks Alex to spend time with Lily; Mark and R.J. start a competitive game of darts to bring some excitement to Low Bar.