Tom Cruise must be having a tough time these days, and it’s not just because of that scandalous biography.

Assuming he watches TV at all, every time he turns it on there’s a new psychiatrist or psychologist working overtime. From VH1’s fly-on-the-Hollywood-wall “Celebrity Rehab” to the tortured yuppie sex lives of the privileged patients on HBO’s fictional “Tell Me You Love Me,” therapy could be the new “reality.” And what’s more real than eavesdropping on someone else’s most intensely private conversations?

HBO’s betting that this strain of video voyeurism runs deep: It’s launching its new half-hour series “In Treatment” (starting 8:30 p.m. Monday) as a five-night-a-week strip, with each night devoted to a different patient’s session. Co-produced by Mark Wahlberg and based on a popular Israeli series, “In Treatment” stars Gabriel Byrne as Dr. Paul Weston, a well-regarded psychoanalyst who works from home and appears to lead a well-balanced life with his wife and children.

It’s not until Friday, when Weston has his own session with another doctor, Gina Toll (Dianne Wiest), that cracks begin to appear in Weston’s smooth veneer. Until then, he’s the sounding board on Mondays for Laura (Melissa George), a woman in a loveless relationship whose boyfriend is pressuring her to marry him; on Tuesdays for Alex (Blair Underwood), a fighter pilot who accidentally killed 16 children in Iraq; on Wednesdays, Sophie, a teenage gymnast in training with major parent issues; and on Thursdays, Jake (Josh Charles) and Amy (Embeth Davidtz), a couple arguing over whether she should abort the baby it took five years to conceive.

As a concept, “In Treatment” is intriguing. The story never leaves the four walls of the session, so it’s far more than the psychological seasoning that Dr. Melfi provided Tony on “The Sopranos” and much more claustrophobic than “Tell Me You Love Me,” where the couples had to leave the office to go have explicit, though boring, sex.

Yet for this concept to work – and for viewers to want to make the 2 1/2-hour time commitment each week – the characters need to be extremely engaging. This is where the dour “In Treatment” falls short. Maybe these walking neuroses will become more empathetic as episodes pass, but, judging from the first week, it’s hard to care about many of them.

The one who is the most interesting, perhaps it’s because he’s on screen the entire time, is the good doctor himself. His complicated professional and personal relationship with Toll, a former mentor a decade his senior, raises several sessions’ worth of questions that should play out through the series.

Byrne is strong as Weston, playing him with a weary resignation that life is not all that it could have been. In fact, the entire cast is solid, especially George, Underwood and Charles.

Still, that may not be enough to make viewers keep their appointments with “In Treatment.”