Castle - Season 2 - Eps 23: Overkill
A robbery-homicide prompts Beckett to invite Demming to assist on a case, giving Castle a ringside seat to their budding romance. When it becomes clear that the two men have very different ideas about how to proceed, the investigation becomes an unspoken competition for Beckett's attention, one in which each man races to solve the case, as Beckett referees between her two admirers.
About Castle

Title: Castle
First Air Date: 2009-03-09
Last Air Date: 2016-05-16
Status: Canceled
Rating: 8/10 (from 1923 votes)
Language: EN
Seasons: 8
Total Episodes: 173
Network: ABC
Genres: Drama, Crime
Production Companies: Beacon Pictures, Experimental Pictures, ABC Studios, The Barry Schindel Company, MilMar Pictures
Synopsis
After a serial killer imitates the plots of his novels, successful mystery novelist Richard "Rick" Castle receives permission from the Mayor of New York City to tag along with an NYPD homicide investigation team for research purposes.
Cast

Nathan Fillion
Richard Castle

Stana Katic
Kate Beckett

Molly C. Quinn
Alexis Castle

Jon Huertas
Javier Esposito

Seamus Dever
Kevin Ryan

Susan Sullivan
Martha Rodgers

Tamala Jones
Lanie Parish

Toks Olagundoye
Hayley Shipton