Kevin Spacey shines in his portrayal of a Los Angeles psychiatrist, Dr. Henry Carter, who's been hitting the booze and drugs pretty hard in the wake of a personal tragedy. After an intervention by his family and friends falls flat, the doctor's father (also a psychiatrist, and played by the great Robert Loggia), sets his son up with a new patient, a teenage girl named Jemma (Keke Palmer) who has faced a tragedy similar to Carter's, in the hope that the case will help his son re-engage in life and better confront his own grief. Despite seeing right through the plan, Dr. Carter grudgingly takes on the case and it indeed starts him back on a more positive, functional path, though things don't happen easily.
An ensemble cast, mostly playing Dr. Carter's other patients, also slowly get drawn into the main story, either directly or through the comments they make about their own problems during their sessions with Carter. An unbilled Robin Williams is a particular standout in his small but memorable role as a movie star confronting his own personal issues (everyone has them in this movie). Indeed, many of Dr. Carter's patients are in the movie business in some way, bringing about an interesting juxtaposition of intense personal issues on the part of some patients (and Carter) and quirky Hollywood shallowness from others.
"Shrink" is mostly serious, but it's lightened a little by Dr. Carter's wry, dry sense of humor (perfectly brought to life by Mr. Spacey), which the character can't help displaying even when he's hurting and wants to be left alone. Keke Palmer's Jemma is also a ray of sunshine in the film, despite the seriousness of her own issues. And, as previously noted, the occasional Hollywood humor, centering around the often insane world of movie deals and star egos, also keeps things from getting too heavy.
I was lucky enough to see "Shrink" on the big screen during its brief and limited theatrical run (thank you, "Ritz Five" theater in Philadelphia!), and heartily recommend it for home viewing when it comes out on DVD.