Mark Jennings

Mark Jennings remains an adult entertainment star decades after his final performance, and just one look at the photo above helps to explain why.  The legendary story of his entrance into smut goes that a young Mark (who was reportedly born in 1966) lived in Michigan and enjoyed hockey among other sports.  Getting friendly-jibed by his buddies in the locker room showers about the big horse meat between his legs, he took advantage of his manly assets by going to work hustling his cock in smut during the mid 1980's.  While there's very little confirmed biography existing about him, it's widely speculated that Mark was probably straight or bisexual; however Mark's actual sexuality remains unknown.  Standing 5'11" with green eyes and a solid 150 pounds, he had a masculine, "freshly scrubbed" attractive face.  
It's Mark work in both gay and bisexual films that made him a top box office draw.  There was a Dan Parks (in 1984 he preformed in The All-American Man) prior to Mark Jennings.  Indeed, he became a star twice--as both Dan Parks and Mark Jennings, largely performing in both gay and bisexual genres with a few straight roles.
 
Multiple stage names are common with male sex performers, but what's unique for that era is that he eventually began to use "Mark Jennings" for bisexual, straight and gay work.   
Dan Parks (aka Mark Jennings)
Not all types of bisexual porn are viewed in the same way in our modern society.  'Female-on-female' bisexual porn (which includes a man at some point in the picture) has enjoyed a long history of commercial success.  Many straight men (who purchase most porn) want to see this type of action and there's been no social stigma associated with men liking to look at naked women, especially when the women having sex together are also craving a stud to join in the party as well.  
Mark's ample manhood being enjoyed by a female friend
It's when there are two men getting it on, sharing one female, where things get uncomfortable for many self-identified straight men.   'Male-on-male' bisexual porn has often been thought of as an offshoot of gay smut, and oftentimes seen as just a cover for closeted gay men.  Unfortunately, this perception of the masculine bisexual male has often been reinforced in bisexual gay smut itself, thanks to the miscasting of effeminate performers in roles where they are playing masculine parts for which they are just not believable.    
 
Looks like this lucky girl gets to polish the Jennings family jewels

All of this helps to explain the popularity of a model like Mark Jennings, who effectively performs in both the straight and gay sex scenes.  In his work with other males, he's usually cast as a straight guy being orally serviced before penetrating his 10.5 inch penis deep into his partner (however, he did perform as a bottom as well).  In his work with women, he equally seems to be enjoying himself.  
Factor in his large cock and a star is born, no matter who he is fucking.  Fans of him performing as Dan Parks followed Mark over to bisexual smut.  
 
Mark Jennings performance in 1985's Best Friends with Jeff Cameron became a hit.  Reviewers noted that the situations and activities were much more believable than most male bisexual porn.  Cameron, who had real chemistry with Jennings, would not return Mark Reynolds’ sequel, Best Friends 2 in 1988.  As an interesting side note, Jeff Cameron appears to have only ever been featured in Best Friends and then retired from the industry.
 
Mark appeared in more than 28 adult films. Unknown is what happened to Mark after he left the business.  Please stay tuned for part two.