In Season 20 of NCIS, team captain Alden Parker faced personal and professional challenges, including being falsely accused of murd3r and dealing with his past. Season 21 may see Parker progressing, potentially reuniting with Senator Constance Miller or facing his unresolved feelings for ex-wife Vivian. His romantic life, strained relationship with his father, and guilt over a past case could be further explored. Fans anticipate seeing Parker continue to evolve, balancing his personal struggles while remaining a dedicated agent for the team.