On Criminal Minds, Jennifer Jareau (JJ) ultimately ends up with William LaMontagne Jr., a detective she meets in the season five episode “Parasite.” Their relationship develops across seasons, survives deployments and personal crises, and becomes a cornerstone of JJ’s arc. This overview focuses on her primary partnership, tracks key milestones, and notes other meaningful connections, offering a durable explanation of JJ’s romantic trajectory for long-term viewers and newer audiences.
Primary Relationship: William LaMontagne Jr.
JJ’s central romance is with William LaMontagne Jr. (played by Josh Stewart), a New Orleans detective they meet in season five. Their connection begins professionally during a case, then deepens into a committed relationship despite geographic distance and the demands of FBI work. Their bond is portrayed as resilient, marked by trust, loyalty, and mutual support. Across seasons, they navigate deployments, life changes, and family milestones, culminating in marriage and the birth of their twins.
Key Relationship Milestones
Their timeline includes several pivotal moments that define the partnership and demonstrate its evolution under the show’s long-form storytelling:
| Season / Episode | Event | Narrative Significance |
|---|---|---|
| Season 5, “Parasite” | JJ and William meet | First connection and initial chemistry |
| Season 6 | Long-distance friendship and support | Builds emotional foundation amid cases and personal struggles |
| Season 9 | Reunion in “The Inspired” and relationship confirmation | Transition to official couple, acknowledging deep feelings |
| Season 10 | Marriage and birth of twins, Henry and Josie | Commitment and family formation; major life change |
| Season 15 | Final episodes show them as a stable family unit | Established partnership and enduring relationship |
Other Notable Interactions and Feelings
Before William, JJ has moments with other characters, but these are largely situational or underdeveloped. Her friendship with Dr. Spencer Reid contains warmth and mutual respect, with brief romantic tension in earlier seasons, though it never transitions into a relationship. Early in the series, there is a subtle connection with Jason Gideon, but this remains largely professional and respectful. These interactions highlight contrast, reinforcing that her lasting, central partnership is with William.
How JJ’s Relationship Evolves Over Time
The show uses JJ’s partnership to explore themes of communication, trust, and balancing personal and professional lives in high-stress law enforcement. Their relationship endures long deployments, shifts in team dynamics, and individual growth. The writers frame William as someone who understands the unique pressures of JJ’s world, providing stability without diminishing her ambitions. This evolution supports JJ’s character development and shapes her ongoing arc across the series.
Context Within the BAU Team Dynamics
Within the Behavioral Analysis Unit, JJ’s personal life intersects with team dynamics, often influencing case perspectives and unit cohesion. William’s presence as a steady, supportive figure indirectly strengthens JJ’s role as liaison between the team and families of victims. Her decisions and emotional resilience contribute to the group’s effectiveness, and her partnership reflects the series’ broader focus on how personal relationships impact professional responsibilities.
Status and Continuity in Later Seasons
In later seasons, JJ and William maintain their marriage and family life, even as the team faces evolving cases and personnel changes. Their twins’ upbringing, career demands, and personal challenges are addressed with continuity, showing adaptation without undermining the core relationship. This sustained portrayal ensures that JJ’s romantic outcome remains consistent and relevant to long-term viewers, offering a dependable reference point for her character beyond individual cases.