In episode 8, season 2, after Virgil lost it a bit towards the reporters interviewing after four of his men got killed, did we catch our first glimpse of bob Kirkland? You can see someone getting out of a black vehicle, he really looks like BK. suddenly, Virgil decides to retire. Whether or not bk is actually red John is yet to be seen, but we know he's involved heavily.

A lot of people seemed to think that patrick ,a twin,
a split personality,and  alex jane maybe even danny jane
 might be red john....BUT  has anybody considered this
 posibility...PLASTIC SURGERY??? the frase  "  you don't
 know me but i know you " AND THE "i want to retire,get
myself a new face,new name new identity.i have the resources"
 got me thinking...what if patrick's other brother jimmy who
is supposed to be dead is alive and jane doesn't know it?what
if somebody related to him from his past changed his appearance?which
would explain the "happy memory"

Kirkland is Red John. But before that, let me debunk some theories that Lisbon works for Red John (I'm assuming the ludicrous theory that she IS Red John can now be completely ignored because of what Heller said that RJ is one of the 7 on the list).

Firstly, her character - Jane has correctly read that she's someone who's too gullible, can't tell lies, and gives herself away easily. In the S5 finale, when Sean Barlow teased her about her liking Jane, Jane didn't flinch or react much but gave his usual wry, I-already-know-it smile because of Lisbon's nature of not being able to hide anything.

If you think that she's putting on an act then here I come to my second point - her reactions - if you notice whenever CBI receives an RJ case (just like in the S5 finale), her reaction will be one of sadness, anxiety and worry. In the finale, when she received the call from the first responders, as she was walking towards Jane to inform him, she looked very pensive and worried. When they arrived at the crime scene in the motel, she was looking at the victim in great pain and agony even when Jane was not looking. She was genuinely worried and sad for the entire thing and for Jane. And finally when she was watching the video at the end of the finale, she was horrified and looked extremely taken aback by the fact that RJ could make the list.

Think about it, if she was working for RJ she would've known all these and is there any way she would react in those ways?And, for all persistent sceptics out there, even if she IS working for RJ but kept in the dark by all these, do you think she would've lasted as RJ's companion/accomplice after seeing all his murders and heinous tactics for FIVE seasons?? As for her unexplained wrist injury in the finale, I'm sure the producers will come up with something to explain it in the next season.

Now I come to my point about Kirkland as RJ.

Why do I say so? Just look at all the signs that Bruno Heller has been throwing at us.

Firstly, the limo and his voice - in the S4 finale it was made known to us that RJ likes to travel in or make use of limos to communicate with his henchmen. It says a lot about how Jane has been accurately reading RJ as someone to be a showman, who has an inferiority complex especially towards women (a point to which I shall return later) and would thus like to feel good and powerful about himself by killing those who make him feel inferior (women) in cruel mockery (the smiling face painted with victims' blood) and what other way to make yourself feel powerful than hire a limo.

Now Bob Kirkland traveled by limo doesn't he? In S5x05 (Red Dawn) we saw him talking to Alexa Shultz in the limo, watching her carry out his orders to get CBI to feed him info about RJ stuff. Perhaps that's how RJ has gotten all his info about the investigation on him and is always one step ahead? And then there's the voice. From all the 7 suspects none of them have a natural voice that is similar to that of RJ as heard in the S2 finale when he helps kill Jane's abductors. From this we can assume that the voice is put-on. And Heller has showed us in the limo scene in S5x05 that Kirkland is perfectly capable of putting on a high-pitched voice (whether it was accidental, I don't know) when he said "Thank you" to Shultz - is Heller trying to hint to us something?

Secondly, the point I said I'd return to, his behaviour around women - I believe there's a reason why the writers/Heller showed the scene in S5x19 (Red Letter Day) of Lisbon and Kirkland having a chat over coffee - it's obvious that Kirkland has difficulties talking to women, and even Lisbon finds it awkward. But he isn't when it comes to RJ at the end, as he slipped the question in of whether there were any "new lines of inquiry" on RJ - a stark difference from his disinterested, unresponsive and awkward style of talking about growing up and his life, etc. Isn't there a clear parallel to how we know RJ to be as read by Jane - inferior and shy around women, dates a blind girl because he's unconfident and therefore kills women to satisfy himself? And then suddenly he becomes so interested when RJ is mentioned!

Thirdly, other signs - in the episode when Lorelei was killed, for a moment the camera briefly shows Kirkland at the scene looking around, surveying everyone including Jane and looking a tad suspicious from my point of view. Is it because, as RJ, he wanted to revel at Jane's reaction to the fact that Lorelei is dead, mock him for being one step ahead, or perhaps he wanted to keep abreast of the latest developments since it's his "internal matter"? There's also the scene at the end of (S5x19) when Kirkland is in his apartment and he's drinking the same drink that Jane drank during the anniversary of his wife's and daughter's murder!!! Is this a John/Jane parallel that Heller is getting at? Fast forward to the last cutscene and Kirkland is done with his project board on whatever Jane has detailed on RJ's history and the setting is made and the camera positioned such that Kirkland's shadow looms over the board - what is Heller trying to tell us? That Kirkland is responsible for all those murders, responsible for everything, the man who oversaw all of those? And what about the infamous shaking of hand in S5x07 when Kirkland also remarks, eerily, "But I know you" and then one of RJ's theme music play ominously in the background? These are very obvious clues that Heller's throwing at us! And if you suspect that it's "too obvious", perhaps Heller already knows we would be thinking this way and is using reverse psychology on us?

Of course, there's also the theories about Jason Lennon - why did he not recognise Kirkland if he is RJ? Couple of possibilities: Firstly, it may be that RJ (Kirkland) did not give orders directly to Lennon but through some other henchman (perhaps Reede Smith, his possible FBI friend?). Or secondly, Lennon's memory has not fully recovered after being shot or he had been hypnotised by RJ before to the effect that if Lennon sees him in person he's not supposed to recognise him.

Then there's also the thing about the list that RJ made - how could it be Kirkland when he got Jane's investigation trail AFTER Lorelei has died and therefore after they made the video? I believe the answer to this is: Kirkland has always been tracking Jane (remember how he got Alexa Shultz to tell Minelli to inform them about the RJ investigation?) and would therefore know who Jane's met, who shook hands with him, etc. to the extent that he could make a list and narrow them down to the same 7 suspects because like Jane, he would know only who possibly could be at all the RJ murder scenes so far (Jane explained in the S5 finale that's how he got down to the 7). Like RJ, Kirkland would be meticulous and always planning ahead, reading Jane's mind very well because like Jane he is also a Mentalist.

Kirkland also fits RJ's physical profile very well - he's of average height, he's of age to have committed the Visualize barn murders (actor Kevin Corrigan is 44 years old), he has short hair, can put on an odd, high-pitched voice (explained earlier), and he's of relative build to have the strength to carry out those murders. His position in Homeland Security would also give him a lot of access to much information and authority to carry out the seemingly-impossible things that RJ did to be always ahead of Jane. Brett Partridge, on the other hand, doesn't, Gale Bertram and Bret Stiles don't fit the physical bill, it would be too anti-climatic for Reede Smith and Thomas McAllister to be RJ (they're running a show, they wouldn't want to lose viewers), although Ray Haffner can be debatable, but my gut feeling is that he isn't because there's not much emphasis on him in the episodes.

There you have it, Bob Kirkland is the one.

bob Kirkland have a unique personality in the show . they always made him looks like arrogant , cold , and a sick person . and red john is 100% a sick person , he draws a smiley face at the wall with his victims blood after he enjoys killing them . bob shook hands with Patrick , and do you remember when Patrick asked him " do I know you ? " he said " no , but I know you " with a creepy look on his face and an evil smile . bob also killed that guy in the hospital and he was afraid that know who he is ... 

Hey guys!

Since it's been 5 seasons already I think it's fair for you to know who Red John really is, no BS, no nothing. I have a friend who works at the show and is in a very good position and he told me Kirkland is the one.
Sorry if that disappointed any of you, but I think it's an ok suspect, don't you?

Something else struck me:
In an EW post-S4 finale interview, Bruno Heller was asked, 'Will you cast Red John next season?', to which Heller replied, 'He might already have been cast. You might already have seen him'. If we take that as it is, the likes of Kirkland and Smith don't make sense since they first appeared in S5. However see how Heller plays with the words 'cast', 'He' and 'him' in reference to Red John: 1) Of course Red John has already been cast way back in S1, since there was or were actor/s already playing him in the few Red John scenes in S1 to S4. It follows then that 'he' i.e. Red John, has been seen by us (though never in full).

2) The question was asked if he will cast Red John in S5, so if Heller meant that he already casted THE actor to play Red John by the time the interview took place, Kirkland certainly qualifies. His statement 'You might have already seen him.' also qualifies because 'him' here would still refer to the character 'Red John', not so much the actor playing 'Red John'.

3) Heller said in the same interview that, ‘...if in season 5 we just opened a door and said “tah-dah!” and it was some mid-range actor, that would be disappointing.’ No way should Kevin Corrigan be considered a mid-range actor. If anything, he is a character actor, given his range of work. So, Kevin Corrigan coming in only in S5 to play Kirkland/Red John, makes a lot of sense. How could you be disappointed by a character actor playing the main antagonist in the story? Consequently, this possibility then disqualifies the other actors who were introduced between S1 and S4.

To answer the question of how Red John came to know of Jane's 'happy memory', a lot of theorists have come out to say that the answer is to be found in the time Jane spent in a psychiatric ward. This is highly possible.

We found out in the flashback episode 5x18, that Kirkland had FBI work with CBI to keep track of Jane. Remember how before Alexa Schultz ended the call with Minelli, she revealed a piece of information about Jane's whereabouts after the murder of his wife and daughter: Jane was in 'an insane asylum'. That was of course to plant some doubts regarding Jane's mental health and give a strong push for Minnelli to keep an eye on Jane and update Schultz. How and who else could have told Schultz about that but Kirkland? If we take Red John out of the equation entirely, say Jane's family was murdered by some other killer, I cannot think of any possible reason why the FBI would be so interested in keeping tabs on Jane. However, Jane's family was murdered by Red John and so he became Red John's person of interest. Hence, how the FBI and the need to inform the FBI about Jane's psychiatric ward stay, came into the picture.

The audience were told of Jane's 'stint' in the psychiatric ward in 1x10, of which the time setting is a few years after he started to work with CBI. The setting of 5x18 is a few years before Jane started his CBI consultancy so chronologically no one in the CBI knew of this when Jane first appeared to them, and henceforth, no one Jane worked closely with (except Minnelli) knew of it until 1x10, by Jane's own admission.

Chronologically, that should be when the information about Jane's psychiatric ward stay was first revealed to the CBI. If Bertram was Red John, why would he need the information to be revealed to Minnelli in such a way? Him being Director could have easily issued the directive that Jane be watched.

A few other things I find interesting:
1. When Kirkland supposedly first met Jane in the CBI corridor, he said, “Sorry, Mr. Jane.” and to Lisbon when he asked about Jane when Lorelai escaped from prison, he referred to Jane as 'your Mr. Jane'. Remember how Red John addressed Jane as 'Mr. Jane' in that note pinned to the door? Subsequently as this strange relationship is formed between them over the years, Jane became 'Patrick' to him. Similarly, Kirkland began addressing Jane as 'Patrick' in subsequent interactions.

2. How impossible would it be for the Attic Invasion to have actually happened before Lorelai's murder? Not at all. It could be that chronologically, the invasion took place before Lorelai's murder but plot-wise, it seemed to be after her murder. 5x18 is proof enough that the writers can play with chronology as they see fit, to withhold or reveal important information. What we see is what seems to be but what it really is, we don't know until it is revealed to us.