nostalgia for the 70s continues , as we see a revival of one of the decade's greatest achievements : the marijuana comedy . 
however half baked doesn't quite run with all its brain cells , and will make you appreciate the questionable talents of cheech and chong all the more . 
the plot follows the misadventures of four ne'er-do-well stoners . 
there's the group's unofficial leader , thurgood ( david chappelle ) , scarface ( guillermo diaz ) , brian ( jim breuer ) , and kenny ( harland williams ) . 
kenny gets into trouble , when , while on a munchie run , feeds his snack foods to a diabetic police horse . 
when the animal keels over , he finds himself accused of killing a police officer , and facing a $1 , 000 , 000 bail . 
his friends promise to raise money for a 10% bail bond , but have no idea how . 
that is , until thurgood stumbles upon a stash of pharmaceutical marijuana being tested at the company where he works as a janitor . 
soon the three guys are dealing dope to raise funds , while avoiding the cops and rival dealer sampson simpson ( clarence williams iii ) . 
for a comedy , the film is pretty humorless . 
not that it doesn't try . . . it's 
just that the comic setups are obvious and the payoffs nearly all fall flat . 
the four leads are nearly all playing the same character . 
only williams stands out ( while still performing on the level of his humor-free comedy rocket man ) , but that is because he's imprisoned throughout most of the film , giving a much needed change of pace ( but mostly swapping one set of obvious gags for another ) . 
to help out , the film is packed full of cameos . 
steven wright , tommy chong , janeane garofalo , willie nelson , snoop doggy dogg , and jon stewart all make appearances at one point or another . 
none of them work , beyond the simple " hey , that's _____ " level . 
in fact the funniest work in the film comes from chappelle . 
not as his bland pothead lead , but in his second role , as a pot-obsessed rapper , sir smokealot . 
granted , it's pretty much a one-joke role , and there aren't a ton of laughs . . . but this film needs every one it can scrape up . 
to top it off , and in a move contrasting with the tone of the rest of the film , thurgood is given a love interest , mary jane ( rachel true ) . 
her role is that of the public service announcement : to inform us why doing drugs ( including pot ) is wrong . 
her character seems fabricated merely as a defense to the " your film promotes the use of drugs " camp . 
the film would have been better off by sticking with the " rebel " tone it so eagerly tries to claim . 
yet , in the end , it doesn't really matter . 
watching the film clean and sober , you are bound to recognize how truly awful it is .