DCI Sam Tyler is the main fictional character in the BBC One sci-fi police drama Life on Mars. He is portrayed by John Simm.Sam Tyler is a Detective Chief Inspector (DCI) in the 2006 Greater Manchester Police force. He was born in 1969 and is the son of Vic and Ruth Tyler. He joined the force at the age of 19 in 1988. He was also in a committed relationship with his girlfriend Maya.After being hit by a car, Sam wakes to find himself in 1973 - only four years after his birth. Unsure whether he is in a coma and dreaming, mad, or if he has actually gone back in time, he finds he is a DI in the contemporary police force of the age, starting his first day in the same station he worked at in 2006 only 33 years in the past, and has to prove himself to his new DCI, Gene Hunt.Gene is a man who likes to throw his weight around and thinks of himself as the sheriff in a western. Gene acts first and thinks later, and this results in several punch-ups between him and Sam, who believes in by-the-book policing.Over time their differences complement each other rather than clash, and a series of cases are solved when the two men put their heads together. But Sam, a 21st century police officer, has to deal with a strange world full of cigarette-smoking, gum-chewing, unreconstructed police officers of the early 1970s, as well as punch-now-think-later policing methods and crude forensic techniques, and there are times when he is deeply stressed by this, as well as by recurring hints that reality is not what it seems.In Episode 4 and Episode 8 , Sam meets the younger versions of his mother and father as well as the parents of his girlfriend Maya, in Series 2: Episode 6 . Twice, in Episode 5 and Episode 8 , he actually meets his 4 year old self to which he is horrified. In Episode 8 , Sam tries to get his father to stay with his mother and his younger self hoping this will take him back to 2006 but is horrified to discover his father is actually a ruthless gangster. In Episode 4 , he also has brought down much of the corruption in CID by convincing Gene and the other officers not to take bribes from a local gangster and also turning in a corrupt high ranking officer in Series 2: Episode 2 .Sam deals with many different crimes including drug trafficking, a hostage situation, murders and robberies. He does not just teach a lot to CID like tape recording but learns something from them.In the last episode, the voice of his surgeon appears as a new character, acting DCI, Frank Morgan, who tells Sam that he has amnesia brought on by a car accident and has really been sent from Hyde to infiltrate the rotten A Division. As Gene, Annie, Ray and Chris face a seemingly unavoidable fate when an undercover sting goes wrong, Sam comes out of his coma in the present.However, finding that what seems to be the real world no longer feels realistic, he commits suicide (see below) by jumping from the roof of the police station, and re-appears in 1973 where he is able to save Gene and the team.Sam Tyler turns off the radio when he next receives a communication from 2006 ( It's no good, he's slipping away from us ) implying that he has chosen his fate - to stay in 1973 as his afterlife.According to Ashley Pharoah and Matthew Graham, the series creators, Sam commits suicide when he jumps, this is mentioned in the documentary The End Of Life On Mars which can be found on disc 4 of the series two DVD set.In an interview with the Manchester Evening News called Life On Mars: The Answers Matthew Graham even goes as far as to say that that Sam is now in the afterlife, where time lasts an eternity compared to the few seconds of the suicide jump: The truth is, when I wrote it, what I was trying to say is that he's died, and that for however long that last second of life is going to be, it will stretch out for an age, as an eternity for him. And so when he drives off in that car, he's really driving off into the afterlife. This is confirmed in Ashes to Ashes, where police psychologist DI Alex Drake has been studying Sam's case and suicide. It is also revealed in Episode 1 of Ashes to Ashes, that in Gene Hunt's world, Sam lived another seven years and was a faithful member of the team. Sam died in 1980 during a high-speed pursuit. His car ends up in the river, but his body is never found.In 2006 Sam wears a dark blue suit briefly in the first episode and when he returns in the last episode. For most of the series whilst he is in 1973 he wears a slightly tattered black leather coat with jeans or plain trousers and some boots. His shirts vary from time to time and as the series progress his sideburns are considerably lengthened. This is also seen when Sam awakes from his coma.Sam is a decent person who would never become corrupt. An example of this is in Episode 4 , where he discovers the entire CID are being bribed. He is also very strict, liking to do everything by the book and can be very short tempered with people, although this may just be due to the situation he is in. Sam can also be relaxed, however this side of him is rarely seen as he is usually under constant stress. Sam often pushes others away from him and usually only Annie Cartwright or Nelson can get him to open up.Sam's main relationship in the show is with Annie Cartwright who often helps him when he is under much pressure. He falls in love with her, and in Episode 8 saves her from being killed by his dad in 1973. When he finally arrives in 2006, in Series 2: Episode 8 , he is tormented by the broken promise he made to her when he went to get help, making him end up back in 2006. He eventually commits suicide and ends back up in 1973, saving her and the others. At the end of the show the two kiss and presumably enter a relationship. The other officers in CID have mixed opinions, Chris thinks Sam is crazy at times but often looks up to him and respects him. Ray doesn't like Sam or his twenty-first century policing but in the end becomes friendlier with Sam. Sam is also close to the bartender of the Railway Arms, Nelson, who he often looks to for advice.The most unusual relationship is between Sam and Gene. The two have very different policing styles and at times hate each other but they always work it out. Gene also knows that Sam is completely trustworthy. When he was framed for murder in Series 2: Episode 7 , he rang Sam first, knowing that despite their difference Sam would not rest until he was cleared. Tyler's apparent death after seven years on the team - as related in Ashes to Ashes - appears to have affected Gene greatly.